Reducing Lethal Force Errors by Modulating Police Physiology

J Occup Environ Med. 2018 Oct;60(10):867-874. doi: 10.1097/JOM.0000000000001401.


Objectives: The aim of this study was to test an intervention modifying officer physiology to reduce lethal force errors and improve health.

Methods: A longitudinal, within-subjects intervention study was conducted with urban front-line police officers (n = 57). The physiological intervention applied an empirically validated method of enhancing parasympathetic engagement (ie, heart rate variability biofeedback) during stressful training that required lethal force decision-making.

Results: Significant post-intervention reductions in lethal force errors, and in the extent and duration of autonomic arousal, were maintained across 12 months. Results at 18 months begin to return to pre-intervention levels.

Conclusion: We provide objective evidence for a physiologically focused intervention in reducing errors in lethal force decision-making, improving health and safety for both police and the public. Results provide a timeline of skill retention, suggesting annual retraining to maintain health and safety gains.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Arousal
  • Biofeedback, Psychology
  • Decision Making / physiology*
  • Female
  • Heart Rate*
  • High Fidelity Simulation Training
  • Humans
  • Interrupted Time Series Analysis
  • Law Enforcement*
  • Longitudinal Studies
  • Male
  • Occupational Stress / physiopathology*
  • Parasympathetic Nervous System / physiology*
  • Young Adult