Why is it so hard to free wrongfully convicted people from prison?

It’s common to hear stories like that of Adnan Syed, who has maintained his innocence through 23 years of imprisonment on a murder conviction and whose story was chronicled through the viral true crime podcast "Serial." A judge recently vacated his conviction because prosecutors withheld information that would have exonerated him.

We've all read these stories. We've seen these pictures of innocent prisoners leaving the gates with their hands aloft, and their faces triumphant. But what's less well-known is why it took so long to get there. We know what put them there in the first place.

We know that eyewitnesses make mistakes. We know that police interrogation tactics can induce juveniles and people with cognitive deficits to falsely confess to crimes they didn't commit. We know that police and prosecutors hide evidence, that defense lawyers are overworked and sometimes underperform and botch their trial strategy. We know about dubious forensic evidence, junk science that can be overvalued by jurors.

But why does it take so long after you've assembled compelling evidence of innocence to convince a judge or a prosecutor to release the person? I know this firsthand. About 20 years ago, I ran the day-to-day operations of a small innocence project in New York. It was the Second Look Program at Brooklyn Law School, where my students and I investigated and litigated claims of innocence by New York State prisoners. And time and time again, we'd find really powerful new evidence, evidence pointing to an alternative perpetrator or maybe a recantation from the main prosecution witness at trial. And judges and prosecutors wouldn't take a close look. Out of those frustrations, I think, this book emerged as I began to research this phenomenon.

https://www.wgbh.org/news/local-news/2022/09/27/why-is-it-so-hard-to-free-wrongfully-convicted-people-from-prison