Three recurring contributors to wrongful conviction are the subject of a Pacific Standard article (here) based on a paper (here) by Steven Drizin, co-founder of the Center on Wrongful Convictions for Youth and Richard Leo, a noted social psychologist.
The first of these sequential errors is the selection of an innocent person as the (often sole) guilty suspect. The second, “coercion error” is pursuing “a guilt-presumptive, accusatory interrogation that invariably involves lies about evidence and often the repeated use of implicit and/or explicit promises and threats…” And the third, “contamination” occurs when officials reveal non-public details of the crime to the suspect, which are later used as evidence of guilt.
Perceived built-in safeguards have been ineffective in eliminating wrongful conviction or—as evidenced by the failure of the appeals process in 300 DNA-proven wrongful convictions—in identifying and correcting conviction error post-conviction. The article calls them “like speed bumps at best.”
Bottom line: These lessons should be applied not in a blame game but in garnering the support of all involved in criminal justice to advance best practices, accuracy, and fairness in the system. Both the article and the paper are worth the read.
Wrongful Convictions Blog 
The Pacific Standard article is dynamite! It is “spot on” on so many issues. I’m keeping this one for my archives.