Abstract
This exploratory study investigates offending patterns of perpetrators of serious sexual assaults (SSA) who were not initially identified at the time of the offense. Thirty-eight adult male offenders were identified through Operation Advance, a phased approach program that forensically reviewed historical sexual offense cases submitted to the UK Forensic Science Service during 1989 to 1999. Results indicated that approximately one-third of the SSA offenders received a post-offense conviction for a sexual‐contact offense. Results showed greater chronicity and versatility of the subsequent offenses for those younger index offenders. Explanations for the findings are discussed with implications for suspect prioritization.