What It Takes to Prove the Truth
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A massive car bomb exploded outside of a large federal building in downtown Oklahoma City, shattering that building, killing children. Oklahoma City, take a look at this picture. This is our tower cam shot, a plume of smoke rising in the air. The bombing in Oklahoma City was an attack on innocent children and defenseless citizens. It's about half of the building that is literally hanging, and at the bottom, the bottom two floors are just stacked debris.

For Kathy Sanders, the days after the Oklahoma City bombing were filled with a deep sense of loss and unspeakable grief. Her two grandsons had been killed in the attack on the Alfred P. Murrah Federal Building, along with 166 other people.

Thirty years ago, in April of 1995, Kathy watched as rescue workers swarmed the bomb site, digging through the rubble for survivors. She waited anxiously while federal agents hunted for those responsible. Was this the work of international terrorists? The news that was trickling in suggested otherwise. Kathy was numb with sadness and shock.

She invited other family members of victims over for dinner. And that night, another emotion crept in. Doubt. One of the young mothers, Renee Cooper, she said when she dropped her son off that morning and he was killed, she said, I saw the bomb squad downtown. We didn't believe her. Why would a bomb squad be there before the bombing had happened?

Kathy dismissed the information, but it had planted a seed of distrust. Most of her attention at that time was still captivated by a massive manhunt for John Doe No. 2, a man witnesses said they had seen with the main suspect, Timothy McVeigh, who was already in custody. And then in a matter of weeks, they come out to the FBI and says, you know what, we made a mistake. There is no John Doe No. 2.

Kathy says more things like this kept happening, and leading up to McVeigh's trial, her trust in the investigation faded, as did her husband's. Now, as I'm watching all this happen, my heart is so broken, I'm dying. But I'm watching my husband's anger. He's mad at McVeigh for blowing up the building, and he's mad at the federal government because he doesn't believe he's been given the truth.

So instead, Kathy took it upon herself to find answers. 30 years later, she's still tracking down evidence and pursuing leads. Well, I felt like I deserved the truth. The truth. What does that really mean? And when do we consider something to be true?

Often it relates to evidence or proof, something that convinces us and eases our doubts. But what kind of proof we'll accept can vary greatly depending on the situation. On this episode, we'll explore proof and how it affects our perception of what's true.

To get started, let's stick with the Oklahoma City bombing, a domestic terrorist attack that was fueled by a deep hatred for the federal government and then fueled distrust in a federal investigation that lingers to this day. Grant Hill has more on Kathy Sanders' story and what kind of evidence she and other surviving family members are looking for.

On April 19th, 1995, Kathy Sanders woke up and did what had become a favorite part of her daily routine. Walked over to the room where her grandson slept to say good morning.

And when I did, I was startled they weren't in their beds. They weren't in there. Her nerves settled when she found the boys, two and three years old, fast asleep next to their mom, Kathy's daughter Edie, in the next room over. When I flipped on the light, I sang, good morning to you, good morning to you. We're all in our places with sunshiny faces. What a nice way to start a new Wednesday. And the little boys begin to giggle and I'm

Edie and I began to get the boys ready for school, and that's where they spent the last night of their lives. The boys, Chase and Colton, went to daycare at the Alfred P. Murrow Federal Building in Oklahoma City. At 9.02 a.m., Kathy heard a thunderous roar. Unlike anything I'd ever heard in my life, I knew something really bad had happened.

Kathy and Edie both worked in the same office downtown, just around the corner from the Murrah building. I ran down two flights of stairs to my daughter's office, and I opened up the door, and everyone inside her office was lined up looking out the windows trying to figure out what happened. And I said to Edie, Edie, let's go see. So we ran down to their main lobby office,

And when we walked out the revolving doors of our building, it was like we entered the twilight zone. There were big sheets of plate glass falling down all around us. There wasn't a car or one moving in the street. They saw smoke rising three blocks away, in the direction where they had just dropped off Chase and Colton. And I said, Edie, the baby's...

She took off running with me on her heels. They arrived to the south side of the federal building to the sound of three more explosions. And we looked at the north side of the building, and where the daycare once was was nothing but a pancaked pile of rubble. And my daughter fell to her knees, and she began to weep, my babies, my babies. And I knew it was the first time in my daughter's life that she had a problem her mother wasn't going to be able to fix.

Kathy and Edie spent the rest of the morning, as hundreds of other families did, waiting for news. And it came relatively quickly. The worst news. Chase and Colton were dead. We get home. We don't know what to do.

We turned on the TV to continue watching the coverage, and they do a close-up view of a little blue sandal that I'd put on Chase just that morning. And I realized, oh my God, the shoes were literally blown off his feet. One of the fathers of a surviving child died.

He's there by the hospital bed with his boy and he said, "You know, we just prayed and asked God for a little boy to hold and God answered our prayer. Isn't this great?" Well, for us, that was like a kick in the gut. Kathy knew she'd say the same thing if her grandsons had survived, but they did not. And that made her and her husband ask questions. Questions about God and the nature of good and evil.

But soon, other questions emerged about the government, the investigation, and what had really transpired on that horrific day. Those questions started a few days after the bombing, when Kathy organized the dinner at her home for the other families who had lost children at the daycare. And one of the moms mentioned seeing bomb squads downtown in the morning.

We didn't believe her. It just didn't make sense. Yet the mom insisted. How do you know? How do you know it was the bomb squad? She said they had big blue letters on their jacket. And my husband was incredulous. He went down to the fire department the next day, and he asked the chief, the fire chief, did the city know it was the bomb squad downtown? The fire chief said, oh, absolutely not. Our bomb squad wasn't there.

But it wasn't just that mother. ABC News later found others had also reported seeing bomb squad teams before the attack happened. The bomb squad in this company newsletter, in this inter-office article by a county worker, and in a small town newspaper story. It wasn't long before the fire chief backtracked. And he said, you know, I just made a mistake. It turned out the county did have its bomb squad truck downtown that day.

The team was scheduled for routine training, but someone used the truck for unsanctioned stops. "Our guys were just running routine errands and stopped to get a cup of coffee. We didn't know what to believe." Because to Kathy and her husband Glenn. That coincidence still did not explain all the other bomb squad sightings downtown that morning.

what looked like armed search teams and bomb-sniffing dogs. We saw officers going through the bushes and looking in these windows at the bottom of the courthouse here, say no more than seven. Investigative journalist Andrew Gumbel co-wrote a book on the bombing in 2012 and dug through thousands of pages of records and government reports. She

He knows how tricky memory can be, especially for those who are asked to recall scenes from what would become a giant media event.

But he discovered there might have been something to those sightings. Another bomb squad unit was in Oklahoma City that morning, one from the state, as well as a team from the U.S. military, sent in all the way from New Mexico. I never got to the bottom of why they were sent. I've never got to the bottom of what they did, if anything, at what point they were told to go home. In fact, the

Andrew says in the days leading up to the attack, warnings were exchanged between agencies. There was vague chatter that something was up. It's not clear if it was a generalized warning against federal courthouses, if it was a specific warning about Oklahoma City. This we do not know. A lot of those warnings circulate all the time. So, you know, it's important not to attach too much importance to it necessarily.

In the early days after the bombing, Kathy and her family knew none of this yet.

But they did know some of the details that were coming out about the perpetrators. By then, authorities already had Timothy McVeigh in custody. The skinny 26-year-old anti-government extremist and white supremacist had been pulled over shortly after the bombing. His getaway car was missing a license plate, and on the passenger seat was a manifesto.

Authorities said the bombing itself was not captured by any security cameras that morning. But McVeigh's description also roughly fit that of John Doe No. 1, one of two men who the FBI said rented a moving truck under an assumed name from a body shop in Kansas days earlier. The truck, whose axle was found in the rubble.

Two days after the bombing, an accomplice, Terry Nichols, had turned himself in. Nichols lived in Kansas and had helped load the truck with two tons of ammonium nitrate and fuel to build the bomb.

But Nichols looked nothing like the other person agents were looking for, John Doe No. 2, an olive-skinned man with long hair and a distinct hat, first seen with McVeigh at the body shop. Two dozen witnesses said they saw a similar man matching that description with McVeigh in Oklahoma City on the morning of the bombing. So the hunt for this mysterious accomplice continued. Who was he, and what was his role in the attack?

The largest manhunt in American history was going on for John Doe II. But not for long. And then in a matter of weeks, they come out to the FBI, says, you know what, we made a mistake. There is no John Doe II. Well, by this time, we already knew there was over 20 eyewitnesses that had seen McVeigh downtown the morning of the bombing.

Many of them described the same dark-skinned man with the tattoo on his arm and the flames on the ball cap that he was wearing. And now they're telling us it was all a mistake. And we're thinking, could 22 people be wrong? Yes, investigators said. According to the FBI, John Doe No. 2 did not exist.

Those witnesses were mistaken. Timothy McVeigh and Terry Nichols were the only people who caused this bombing.

Journalist Andrew Gumbel says prosecutors insisted the case was just that simple, that it had to be. There was a tremendous amount of pressure from on high, which is to say President Bill Clinton, Janet Reno, the attorney general, who said, you know, we can't lose these cases. We need to get the death penalty. We absolutely have to make sure that there is justice for the bereaved population of Oklahoma City.

And the prosecutors described this to me. You know, they said we couldn't fail. At a certain point in the investigation, they had not been lucky in finding other suspects beyond McVeigh and Nichols.

And they decided as a matter of courtroom strategy to focus on them exclusively and to characterize McVeigh in particular as a lone mastermind. That meant no loose ends, no mysterious unexplained John Does. You had this very strong narrative from the federal government, but also from state officials that McVeigh and the person who was acknowledged to have helped him to build the bomb and to assemble the components, Terry Nichols, were the only two significant players.

In 1997, Kathy and her husband watched prosecutors lay out this narrative in real time at Terry Nichols' federal trial. But the couple had grown jaded by the bomb squad saga.

They had no doubt that Terry Nichols was guilty. Still, they listened as his defense attorney poked holes in the idea that he alone collaborated with McVeigh. Then we learned about the Dreamland Motel where McVeigh stayed the week before the bombing. Well, while he was at the hotel, there were people seen coming and going from his room. People investigators said, once again, did not exist.

despite what multiple witnesses had told them. The motel owner, a Chinese food delivery man, and other guests. These seemed like important leads, leads Kathy and her husband thought were simply dismissed rather than disproven. That was problematic for us. Then we learned that the FBI had...

gotten good latent fingerprints from McVeigh's car after he was arrested and from the Dreamland Motel. And when we learned, an FBI agent said on the witness stand, no, I took all these prints, but I didn't run them through the computers for a check. And the defense attorneys were like, well, why in the world wouldn't you? And he very sheepishly said, well, it wouldn't be cost-effective.

Why was the FBI letting so many leads go? So many other potential suspects who might have been implicated? She asked this to one of the lead agents who sat next to her in court.

He patted me on the shoulder and he said, don't worry, Kathy. We don't want to give the defense teams any ammunition to point the finger anywhere else. We want to get these two convicted and then we're going to go after the others. They never went after the others. Before the trial ended, less than two years after the bombing, Kathy's husband Glenn died of pancreatic cancer. He was 47. I learned from watching Glenn that

harboring bitterness and anger and hatred in your hearts like drinking poison and expecting the enemy to die. Now, Kathy sat alone in the courtroom, searching for the answers her husband would never know. And her heart started to break for someone else.

Terry Nichols' mom. I realized, you know, she's the forgotten victim. What a horrible thing that her son got so messed up in. And it wasn't long after I befriended her, we began to eat together in the courtroom, eat lunch together, and we sat together in the courtroom. And Terry Nichols, the bomber, became my friend Joyce's son. She never forgot that Joyce's son was a terrorist who helped build the bomb that killed her grandsons.

But she started to see him differently. Not as a monster, as a person who did something monstrous. If others had helped him pull it off, they should at least be treated like he was.

A third man, Michael Fortier, eventually did admit to knowing about the plot. But he struck a deal with the feds, testified against Nichols and McVeigh in exchange for only 12 years of prison time and his eventual disappearance into the Federal Witness Protection Program. For the prosecutors, his testimony was fruitful. Nichols was found guilty on one count of conspiracy and eight counts of involuntary manslaughter.

Unlike Timothy McVeigh, he was spared the death penalty and sentenced to life without parole. The jury for a woman got on TV and she said, we know Nichols is guilty, but we don't know how guilty. So that left me with a lot of questions. The trials came and went. I went back home. I got a letter in the mail and it was from Terry Nichols. And I thought, Lord, I don't want a

I'm not looking for a pen pal, and if it was, I wouldn't be the Oklahoma City bomber. And then I thought, well, who's going to know more about the bombing than the bomber? So I was willing to dance with the devil to get to the truth. I began to write to Terry. Soon, he asked Kathy for her number. He said he wanted to speak with her. So I gave him my phone number, and we began to talk on the phone. And the phone calls were just 15 minutes long, but he could call several times when he was at the county jail.

I mean, soft-spoken, you would never think that the man would have done something so horrific.

And probably had he never met Timothy McVeigh, he wouldn't have done anything. And then I began to go up to the jail to see him. In 2004, Nichols was being held close to where Kathy lived, awaiting his trial on state charges. A final shot for the people of Oklahoma to sentence him to death. Did I forgive Terry Nichols? Yes, I have. Do I think he should be punished? Yes, I do. Forgiveness and punishment are two different things, but I have a friendship with him.

Nichols did not want to die. Kathy said he told her that once his trial was over, once the death penalty was not hanging over his head, he'd tell her everything he knew about the plot, what he remembered about who was involved.

And soon, it seemed like that day had come. Nichols was found guilty on all of the state charges. But again, the jury could not come to a unanimous decision on the death penalty. The rest of his life would be spent at a federal maximum security prison in Colorado, where he agreed to let Kathy interview him for a segment that would air on CBS's 60 Minutes. He told Kathy he trusted her more than any journalist.

The story was supposed to be a follow-up to the show's interview with Timothy McVeigh five years before. But then Kathy got a letter from the warden. Her request to meet with Terry Nichols was denied because, the warden said, it, quote, could pose a risk to the internal security of the prison and to the staff, inmates, and members of the public. Now, Florence, Colorado is the prison that houses the worst criminals in America. Yeah.

How could I possibly be a threat to them? So they wouldn't allow it. Eventually, Kathy said she got word from Terry Nichols' mother, Joyce, that she was taken off of his call list, too. Ever since, Kathy and Nichols have written to one another knowing their letters are screened, unsure whether their full correspondence really gets through. And Kathy's search for answers has continued.

She wants to know if there were others who helped McVeigh and Nichols pull off the bombing. She also wonders about the involvement of undercover federal agents, people who might have tipped off those bomb squad teams a little too late. Well, I felt like I, my husband, and that my grandchildren deserved the truth. So I've continued the investigation over all of these years. She's collected her own statements, asked her own questions—

keeps her own archive.

And helps journalists when they come calling. Journalists like Andrew Gumbel, who started to write his book on the bombing in 2001. And when I came along in 2001, she'd been at it for six years and was able to introduce me to a number of people. That was my starting point. It was a starting point that eventually led Andrew and his co-author to access the full discovery file that the government had handed over to Terry Nichols' defense team at trial.

something no journalist had ever seen before.

And the file posed more questions than it answered, including one extremely confounding question, something Timothy McVeigh's lawyer made a lot of noise about during his trial. Not those witness statements or a lack of security camera footage, but a physical piece of evidence called P-71. So what happened was that about a month after the bombing, there was a federal investigation

who found this extra leg in the rubble. A left leg with a military boot attached to it. And in those days it was a

Andrew says it soon became apparent that the leg belonged to a 21-year-old Air Force cadet who was killed in the attack. She had stopped into the federal building to get a social security card for her baby.

who in the meantime had been buried in her hometown in New Orleans. A decision was made to exhume Lakeisha Levy's body. They confirmed, first of all, that the leg and the rubble belonged to her, but she had been buried with a different left leg.

So then the question was, who did that belong to? Maybe that leg belonged to John Doe No. 2, or any other conspirator who may have been killed in the blast. At trial, McVeigh's lawyer argued the leg suggested the presence of another bomber. Prosecutors said it likely belonged to one of eight victims buried without a leg. Andrew's sources in the FBI told him they were really confident about this theory.

that they had even narrowed it down to a single victim. But the only thing that would settle the dispute was a DNA profile, a sample that could either be matched to a victim or identified as an unknown suspect. Unfortunately, the state medical examiner testified that his office was unable to obtain a DNA profile from the leg because it had already been embalmed.

Decades later, however, in 2015, that same office told a local news outlet something different.

The office did obtain a DNA profile of that leg after all, and it did not match any of the victims it was tested against. Nor was this DNA profile ever provided to defense teams. This extra leg has bothered Kathy Sanders since she first found out about it during the trials. Because they don't know who it is. It could be a bomber. We don't know. Terry Nichols also seemed to think it was potentially crucial.

If you really want to get to the bottom of the OKC bombing, he wrote to Cathy in one letter, then do a genealogy test on that leg.

Nichols wanted to apply modern science to crack the case, forensic genetic genealogy. It was the same technique that led to the apprehension of the Golden State Killer in 2018. Using public DNA databases built from consumer ancestry kits to identify a suspect's relatives based on their DNA profile, Cathy had the same idea.

So recently, she called up the medical examiner's office and asked for a copy of that DNA profile. I said, well, I'd like a copy of it. Oh, well, I'm sorry, I can't share that with you. She filed a formal request and received the same response. If there's nothing to worry about P71, then let's do the DNA, you know? If you've got the science and aren't allowed to use it, then you're just up a creek.

The office apologized, saying legally their hands were tied. According to the law, the only person who could order that kind of testing was an interested party in the case. Someone like a defendant. Someone like Kathy's unlikely ally, Terry Nichols.

Kathy has spent three decades collecting evidence, looking for truth.

She's written books about forgiveness and healing and participated in documentaries about her hunt for more evidence. Her most recent book came out this year, Shadows of Conspiracy, the untold story of the Oklahoma City bombing. Kathy says she won't rest until she feels like all of the evidence has been reviewed and acknowledged and until she feels like the story of the bombing is complete and true. ♪

That story was reported by Grant Hill. Coming up, as a mathematician, Adam Kucharski thinks a lot about proof. But he also knows that lots of factors can sway what we believe to be convincing evidence. Proof often has this urgency to it to understand what you're dealing with. That kind of intensity of time pressure can interact with, you know, often quite uncertain evidence. That's next on The Pulse.

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Imagine you're stranded at an airport, along with millions of other travelers stuck at airports all over the world. A volcano in Iceland has erupted, and a giant, lingering ash cloud has shut down much of the airspace over the North Atlantic Ocean because of safety concerns. What would happen if ash got into a plane's engines? Would that cause engine failure mid-flight?

You could be stuck for days, even for weeks. What kind of proof would you want to see that it was actually safe to fly? Mathematician Adam Kucharski was one of the travelers stuck during that volcano eruption in 2010. He was hoping to get home to London. I was actually in the Caribbean at the time, so I think I tend to lose a bit of sympathy from people when they find I get stranded out there.

As passengers waited for news, airlines and officials were trying to gather information and data. Governments were very eager to get proof that things were safe and airlines were very keen to get proof that things weren't safe. Eventually, KLM, the airline Adam was flying with, sent up some test flights without passengers.

When they got back, they didn't find any evidence of damage and kind of more flights went up, more airlines started kind of testing things and starting to understand at the fringe of the cloud actually what was the extent of risk and then starting to resume flights once they had more confidence what that looked like. This incident stuck with Adam. He's trained as a mathematician, so he knows all about the principles of proof. But this was a different situation. Adam?

I think one thing that really struck me about the story is not only how people's perception of what needs to be proved can be quite difficult, but also proof often has this urgency to it. I think a lot of us are familiar with how science works and we get this kind of accumulation of knowledge over a period of time. But when you've got a situation like that where you've got millions of people stranded abroad, you have an urgency to understand what you're dealing with.

accumulate evidence, have sufficient confidence in that evidence to take action. I think for me, it really stood out as an example of how that kind of intensity of time pressure can interact with often quite uncertain evidence. Adam has a new book out. It's called Proof, The Art and Science of Uncertainty.

How do you think about proof? We tend to think it means something is true without a shadow of a doubt. You know, we've given you proof, here it is. But once you start to pull at this word and what it is, it becomes much less defined. I think because my background's in mathematics, I think growing up I had this natural tendency to think of it in terms of we can approach this universality of truth and once it's fixed, it's going to be solid forever. And

Even within that subject, the history of maths isn't just one where you've just got that certainty and it's been faked. It's been layered upon the societies through which that proof has been created, even in some cases the politics amongst the mathematicians of how these things have progressed. One example that stands out in European maths is a lot of it was informed by geometry. So a lot of what propagated was very much about our intuition about the physical world. So even things like negative numbers are

were often avoided or kind of reluctantly used even into the 1700s because there's not really a physical intuition for what a negative, you know, what's a negative triangle. That doesn't really make sense. Whereas, you know, in Asia, in places like China, there'd been a lot more derivation of maths around things like finance and debt where these concepts made more sense. So I think even for me, that was quite striking that you've got this subject that

is thought of as pure certainty, but actually ending up with things that are deemed proven to kind of fall away with these awkward examples. But I think then going more broadly into science, I think realizing that there's a lot more complexity to how we approach these things. And it's not just about this kind of 100% certainty, but how we manage these situations with the inevitability of error and how can we still do useful, valuable things regardless.

And how do you see the relationship between proof and truth? Because sometimes there is proof or there seems to be proof, but it still doesn't always mean something is true or true all the time. I think one of the things we see quite a lot in science is the need to act on evidence, even if that evidence may be revised in future. And those...

There's quite a nice line by Austin Bradford-Hill, who did a lot of early work on smoking and cancer. And crucially, that's a problem where you can't run a randomised trial in the way you might for a new drug. You can't make people randomly take up smoking to look at the effects, both for ethical reasons and also just the time scope involved. And Bradford-Hill made that point that

Science is always subject to being revised in future, but you have to take action on the evidence that you have available. Do we over-rely on what we call proof? You know, is proof perhaps not as important as we make it out to be? I think there's a lot of things in life we want to know work. And whether we're talking about things like medicines, things like technologies, having a high level of confidence is

I think one thing that we can get stuck on, and you see a lot in public discussions, is using one type of evidence where that might not be most appropriate for the thing at hand. And so it might be in some cases...

trying to demand a level of evidence that just simply isn't feasible for that kind of problem. I think also, you know, as people, there's only so much information we can process. You know, we don't have to read up on how planes work before we get on them, or we don't have to, you know, dig into loads of clinical trial data every time we go to a doctor. They're kind of relentlessly telling people that they shouldn't believe what they should see and they should doubt lots of things. I think a lot of the evidence we see about information consumption suggests that

It can push people into excessive doubt. And that's not what, you know, we don't want people to believe lots of things that are false. But equally, a lot of living healthy, useful lives relies on us trusting that things are true. Adam Kucharski is a professor of infectious disease epidemiology at the London School of Hygiene and Tropical Medicine. His new book is Proof, The Ardent Science of Uncertainty.

Coming up, science relies heavily on proof. But what happens when that proof unravels? This is so painfully obvious that she's making this stuff up. No one watches her. She doesn't record anything. That's next on The Pulse.

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This is The Pulse. I'm Mike and Scott. We're talking about finding proof.

Scientific research relies on specific methods to find evidence, experiments, trials, and documentation so that other scientists can replicate both the experiments and the findings. But what happens when that process fails? Alan Yu looked into a case where a high-profile study in marine biology made a big splash and then even bigger waves when the findings fell apart.

Paul Leingang was a biology student when he first learned about a major discovery in the fields of marine biology and climate change. A landmark study in 2014 found that acidic ocean water, a side effect of global warming, could cause fish to swim towards their predators instead of away from them. And I was like, oh my god, that is terrifying for what this means for coral reefs.

It suggested that climate change not only made the ocean less hospitable for many creatures, it could cause them to swim towards their death. And I had gotten scuba certified and fallen in love with the ocean, and I said, this is it. This is what I want to work on. He applied to graduate school at the University of Delaware to work with the scientists who had made this discovery. Danielle Dixon, a

a young rising star in marine biology. She wrote about her research in Scientific American in 2017, saying, quote, ocean acidification is messing with fishes' minds, end quote. Paul was accepted, and at first, the PhD program with her seemed great. The lab had fieldwork in Fiji in the South Pacific, so he got to fly there to do research.

The water is like glass clear. I mean, you can see for just 500 feet, like in any direction. It's beautiful. It really is like paradise. Part of the research involved a survey of what types of fish were in the coral reefs. The biodiversity in Fiji is incredible. There are people who will tell you it is impossible to ID fish.

Paul says that's true. Identifying the fish in real time can be quite tricky because these coral reefs are teeming with many different species.

Paul wanted to record videos of what he was seeing, so he could refer back to the footage later and use a guidebook to identify the fish. But his advisor said no. Danielle specifically told us we were not allowed to film anything. And so I had to write down all these descriptors of some of these fish that I would see for just a flash of a second, and

And it was really, really difficult. And I would spend hours and hours pouring through these ID books trying to remember what I had seen based on these notes that I took underwater. The ban on videos seemed odd. And things got stranger after he got back to Delaware. By now he was a few years into his PhD. But he had never actually seen Dixon do an experiment before. Now came the moment where...

She's doing them and I'm like, okay, I'm going to watch. She was working on the kinds of experiments that produced her famous results, that ocean acidity had an impact on how fish behave.

This particular experiment involved clownfish that live in stinging anemones. Nemo from the movie Finding Nemo is a clownfish. The stinging anemones do not hurt the clownfish, but protect them from predators. The experiment was about whether or not baby clownfish would be able to recognize and swim towards the smell of anemones to find shelter. Because if they're out in the vast open ocean...

They can't see the anemone that's 900 meters away, but they might be able to smell it and then they can follow that smell. To picture what the experiment is like, Paul says to imagine two water slides. One has clear sea water, the other has sea water with the smell of anemones.

Paul says Dixon made different samples of seawater with varying concentrations of the anemone smell and looked at whether the fish would swim towards the smell or not. What he found unusual was how quickly Dixon was running through these experiments. He says each of them is supposed to take nine minutes, but she completed them in four minutes.

Paul says he saw her do an experiment for four minutes, but writes it down as if she had been doing it for nine. It was like this veil got lifted where I realized she's making things up. Like she's not doing a full trial and she's recording a full trial's worth of data.

There had already been other scientists who were skeptical of her work, and Paul says now it all clicked. I felt like an idiot. This is so painfully obvious that she's making this stuff up.

No one watches her. She doesn't record anything. Paul talks to the other graduate students who were equally shocked at what he had seen. He talks to another professor he was working with, and more high-ranking staff at the school got involved. He did not confront her directly. I don't think that would have gone well. To be honest, I was scared.

You know, like she had a lot of clout in the marine biology world. Paul filed an official allegation of research misconduct in January 2020.

other people had also been skeptical of Dixon's findings. Timothy Clark, an ecophysiologist at Deakin University in Australia, took note of the research when it was first published. It was the most profound findings that I'd ever seen in biology in my career. He and other researchers tried to replicate the experiments Dixon used to make her case, to see if there was more they could learn.

When we attempted to do that and we replicated their experiments as best as possible, nothing worked. They could not reproduce the same incredible results.

Timothy and his team thought they must have been doing something wrong, so they tried the experiments again and again. They refined some of their methods, and they also videotaped their work. We were transparent and robust in our approaches because I knew that if we didn't find evidence

They tried for years and could not replicate the original research. In January 2020, Timothy and his team published their findings in the journal Nature.

The title of the article was simple, but a clear blow to Dixon's work. Ocean acidification does not impair the behavior of coral reef fishes. Some researchers, including Dixon, did indeed criticize Timothy and his collaborators for not doing the research correctly.

That same month, Paul Leingang submitted his official allegation of research misconduct to the University of Delaware. The university started an investigation into Dixon's work. She was put on paid administrative leave. The investigation took more than a year. During this time, Paul left the university, the PhD program, and eventually the field.

He moved to Florida and now works for a local housing authority. The University of Delaware found Dixon guilty of research misconduct and said they intended to fire her.

The investigation found that she could not have done the research as quickly as she did, and that she also copied and pasted some data as if she had done multiple experiments. In 2022, the journal Science retracted one of her biggest papers. The journal would not comment on this specific case.

But I did get to speak to the editor-in-chief, Holden Thorpe, about retractions in general. He says when a university contacts the journal to say they did an investigation and came to a conclusion about data that was published, the journal would take their lead from the university and say so in the retraction. We're not an investigative body. We can't say to an author if they don't want to give it to us.

Send us your lab notebooks or whatever it is that needs to be investigated. The university has the ability to do that. He says they will not retract a paper on their own unless they already have all the data they need to decide. The journal Science publishes 750 papers a year and retracts roughly three to five of those. What the public expects from scientists is

The story of Danielle Dixon took a turn in January 2023. A University of Delaware Faculty Senate committee concluded that she should not be fired.

They said, among other things, that she could have done the research in half the time because she, being a world expert in these experiments, was able to do two of them at the same time. This report says that she had made some honest mistakes when copying and pasting data and that she did not intend to make it look like she had done more work.

The panel found that they can see how, quote, such errors could be inadvertently committed, i.e. without nefarious intent, end quote. I contacted the professors on that panel and they declined to comment. I tried to speak to Danielle Dixon directly, but she did not get back to me.

Christina Larson was her lawyer throughout these investigations and is still in touch with her. Christina says that Dixon would not like to comment and that she did nothing wrong.

Christina says the university botched the first investigation by listening to people who did not know what they were talking about. They took the word of her graduate student who hadn't worked on the apparatus over her. Her own expertise was completely disregarded.

The committee took no account of the differences in how research is done. She says the second report, the one from the Faculty Senate Committee, concludes that Dixon did not commit research misconduct.

She says that proves the first investigation was done badly and that the first group did not trust Dixon, the expert, and relied instead on unqualified critics. And in the end, they came up with a really terrible, fairly poorly evidenced case.

finding of misconduct that later when she went to another group of faculty whose charge was to decide whether there was justification to terminate her based on that finding

unanimously found huge flaws in the way in which the investigation had been handled. Danielle Dixon no longer works at the University of Delaware and no longer does research. The university declined to comment on this story, saying only that they do not comment on personnel matters. So where does all of this leave the main claim of Dixon's research, that ocean acidification impacts fish behavior?

The scientists who tried to replicate the work said the effect is negligible. But other scientists disagree. Ocean acidification is doing things. It's just not as necessarily clear-cut. That's marine scientist Andrew Espar from the University of Texas at Austin. He studies how fish interact with their environments.

He says while there were problems with the earlier research, it does not mean the question has to be dismissed altogether. Trying to not just document whether or not an effect happens, but trying to understand how significant that effect is to the outcome of a species is...

It's a real hurdle, not just for ocean acidification, but for really all environmental science-style research. He says what happened with the ocean acidification research is how the scientific process sometimes works. There is an early dramatic discovery that gets a lot of attention. Other scientists build on that work.

some find that the initial discovery is not as dramatic as people had thought. And that leads to more research. Sometimes, you know, you take one step forward, two steps back to get four steps forward. It's a constant push and pull in terms of where the field is going. The way the scientific process played out, it shows that there's a lot of strength in the way that our scientific community works.

That's our show for this week. The Pulse is a production of WHYY in Philadelphia, made possible with support from our founding sponsor, the Sutherland Family, and the Commonwealth Fund. You can follow us wherever you get your podcasts. Our health and science reporters are Alan Yu and Liz Tong. Charlie Kyer is our engineer. Our producers are Nicole Curry and Lindsay Lazarski. I'm Maiken Scott. Thank you for listening.

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