This study investigates career-ending police misconduct that occurs with little or no prior warning. Using administrative data from a large policing agency in the United Kingdom, we examine the predictive value of unsubstantiated complaints and related career characteristics for career ending misconduct. While unsubstantiated complaints were correlated with minor complaint types and overall complaint volume, they showed no clear relationship with career ending misconduct. Among officers with unsubstantiated complaints, however, significant predictors included duty type, frequency of transfers, and, most notably, the presence of secondary employment. A separate analysis of officers who committed “spontaneous” career ending misconduct—without any history of prior complaints—revealed no consistent demographic or career predictors. These findings challenge the utility of traditional early warning indicators among officers without complaint histories. We conclude that early intervention approaches must be refined to reflect multiple misconduct trajectories.