How do wrongful convictions happen?

Research conducted by wrongful convictions scholar Jon Gould of American University identified several predictors that help explain why an innocent defendant, once indicted, ends up erroneously convicted rather than released. These include:

  • A younger defendant
  • A criminal history
  • A weak prosecution case
  • Prosecution withheld evidence
  • Lying by a non-eyewitness
  • Unintentional witness misidentification
  • Misinterpreting forensic evidence at trial
  • A weak defense
  • Defendant offered a family witness
  • A "punitive" state culture

A qualitative review of the cases in Gould’s research reveals how the statistically significant predictors are connected and exacerbated by tunnel vision, which prevents the system from self-correcting once an error is made. In fact, tunnel vision provides a useful framework for understanding the larger system-wide failure that separates erroneous convictions from near misses.