In 2017, Sergeant Mathieu Nadeau oversaw the investigation of a suicide by firearm. An internal investigation found that he violated Attorney General’s Office protocols for death investigations and failed to maintain sufficient competence. Initially, a one-day suspension without pay was determined, but after grievances, no discipline was ultimately imposed. Additionally, concerns about his truthfulness in handling a traffic accident involving Deputy Jones led to inquiries about potential Giglio impairment, though no sustained findings of untruthfulness were made.
[Return to blog post](https://watchaudits.com/sergeant-mathieu-nadeau-york-county-sheriffs-office/)
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