I HAD MISSED THIS: Dr. John Plunkett, RIP. He told the truth about bad forensics — and was prosecuted for it.

Like a lot of other doctors, child welfare advocates and forensic specialists, John Plunkett at first bought into the theory of Shaken Baby Syndrome (SBS). This is the theory that an autopsy on a young, recently deceased child reveals three symptoms — bleeding in the back of the eyes, brain swelling, and bleeding in the subdural space just above the brain — those injuries could only have been caused by violent shaking. The diagnosis gained popularity in the 1990s, then became more common still after the high-profile trial and conviction of British nanny Louise Woodward in 1997.

It’s a convenient diagnosis for prosecutors, in that it provides a cause of death (violent shaking), a culprit (whoever was last with the child before death) and even intent (prosecutors often argue that the violent, extended shaking establishes mens rea.) According to a 2015 survey by The Washington Post and the Medill Justice Project, there were about 1,800 SBS prosecutions between 2001 and 2015, with 1,600 resulting in convictions.

But in the late 1990s, Plunkett — a forensic pathologist in Minnesota — began to have doubts about the diagnosis. He started investigating cases in which children had died in a manner similar to the way accused caregivers had described the deaths of the children they were watching — by short-distance falls. What he found alarmed him. In 2001, Plunkett published a study detailing how he had found symptoms similar to those in the SBS diagnosis in children who had fallen off playground equipment. It was a landmark study. If a short-distance fall could produce symptoms similar to those in SBS cases, the SBS diagnosis that said symptoms could only come from shaking was wrong. By that point, hundreds of people had been convicted based on SBS testimony from medical experts. Some of them were undoubtedly guilty. But if Plunkett was right, some of them almost certainly weren’t.

Naturally, defense attorneys began asking Plunkett to testify. He obliged. The same year his study was published, Plunkett testified in the trial of Lisa Stickney, a licensed day care worker in Oregon. She had been charged with murder for the death of a young boy in her care. According to Stickney, she was in another room when she heard a thud. She rushed over and found the boy on the floor near an overturned chair, with blood coming from his head. But according to prosecutors, an autopsy showed the boy had the symptoms that conventional wisdom held could only have come from violent shaking. Thanks in large part to Plunkett’s testimony, Stickney was acquitted.

The acquittal was another landmark moment in the SBS story. Plunkett was now a threat to SBS cases all over the country. The office of Deschutes County, Ore., District Attorney Michael Dugan responded with something unprecedented — it criminally charged an expert witness over testimony he had given in court. One of the state’s experts also filed an ethics complaint against Stickney’s other expert witness. The actual charges were filed by ssociate District Attorney Cliff Lu — four counts of “false swearing,” a misdemeanor charge related to perjury. Dugan’s office also contacted other prosecutors across the country to tell them that Plunkett was under criminal investigation. It was a pretty obvious effort to silence him — to prevent him from testifying in other cases. No defense attorney was about to call a witness if they jury would also learn that he was facing criminal charges over testimony he had given in court. . . .

Plunkett has bascially been vindicated in the years since his trial. What about the people who went after him? According to his LinkedIn profile, Eric Wassman is now a circuit court judge pro tem. As of February, Cliff Lu was still an assistant district attorney in Deschutes County. Former DA Michael Dugan was soundly defeated in 2010 after 23 years in office, and amid allegations of sexual discrimination and possible wrongful convictions. Dugan appears to have since joined the Malheur County, Ore., DA’s office as an assistant district attorney, where in 2014 he was pursuing a racketeering case against two men for selling medical marijuana. In 2015, Deschutes County endured another forensics scandal — county officials revealed that as many as 1,500 drug cases may have been tainted by a corrupt crime lab analyst.

Yet another reason to abolish prosecutorial immunity. And another reason why my Ham Sandwich Nation piece is still timely.