Understanding Wrongful Convictions

Mistaken eyewitness identifications are the single greatest cause of wrongful convictions nationwide, contributing to approximately 69% of the first 375 DNA exonerations.

• •Cross-racial identification is particularly unreliable
• •Lineup procedures can unconsciously influence witnesses
• •Memory is malleable — stress, weapon focus, and time degrade accuracy
• •Reforms include double-blind lineups and confidence statements

Roughly 29% of DNA exonerations involved false confessions or admissions. Interrogation tactics, mental health, intellectual disabilities, and youth are key risk factors.

• •The Reid Technique and prolonged interrogation increase false confession risk
• •Juveniles and individuals with cognitive impairments are especially vulnerable
• •Mandatory recording of interrogations is a key reform
• •A false confession can contaminate other evidence and witnesses

Unvalidated or improperly applied forensic methods — bite mark analysis, hair comparison, arson science, and more — have contributed to nearly half of wrongful convictions.

• •Bite-mark comparison has been widely discredited by the scientific community
• •Microscopic hair comparison has an error rate of up to 11%
• •Outdated arson investigation techniques led to wrongful convictions for decades
• •The 2009 NAS Report called for fundamental reform of many forensic disciplines

Government misconduct — prosecutorial and police — was a factor in over 70% of recent exonerations. The most common form is concealing exculpatory evidence (Brady violations).

• •Brady v. Maryland (1963) requires prosecutors to disclose evidence favorable to the defense
• •Police misconduct includes coerced witness statements, fabricated evidence, and tunnel vision
• •Prosecutors have near-absolute immunity, making accountability difficult
• •The National Registry of Exonerations tracks misconduct in every documented case

Incentivized testimony from jailhouse "snitches" is one of the leading causes of wrongful convictions in capital cases. Informants receive reduced sentences or other benefits in exchange for testimony.

• •Informants have a powerful incentive to fabricate or exaggerate
• •Jurors often are not told about the deals informants receive
• •Some jurisdictions now require corroboration of informant testimony
• •Tracking systems for repeat informants have been proposed as reform

Underfunded and overworked public defenders, lack of expert witnesses, and ineffective assistance of counsel have contributed to wrongful convictions.

• •Strickland v. Washington (1984) sets a high bar for proving ineffective assistance
• •Public defender offices are chronically understaffed in many jurisdictions
• •Defendants who cannot afford private counsel may spend only minutes with their lawyer
• •Post-conviction access to counsel varies significantly by state