PORT ST. LUCIE, Fla. (CBS12) — A Port St. Lucie police officer resigned while under investigation after walking away from a vehicle containing a man who had shot and killed himself, only to return minutes later as backup.
According to an internal affairs report, 23-year-old Officer Mathew Brown resigned on April 17, 2026, facing sustained findings for neglect of duty and inefficiency.
Surveillance video from the Treasure Coast Church of God Worship Center showed Brown pulling behind a dark blue Porsche at 1:47 a.m. on March 21. Brown shined his lights on the car, ran a license plate check, and walked up to the passenger side.
However, after looking through the window, Brown turned right around and drove off without calling dispatch or checking on the person inside.
PSLPD Internal Affairs RpeortPDF previewPreview PDF
PSLPD Internal Affairs Report
At 2:02 a.m., a second officer stopped to check on the suspicious car and found a man dead inside from a gunshot wound, with a handgun sitting on his lap. Paramedics confirmed he was dead, and investigators ruled the death a suicide.
Sent back to the scene as backup, Brown told the responding officer he had driven by earlier but “didn’t see anyone in it.”
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Body camera footage captured Brown telling the officer to “go blue,” muting both of their cameras for 32 seconds. When a supervisor later pointed out fresh tire tracks in the muddy grass right next to the Porsche, Brown stayed silent, failing to admit they were from his patrol SUV.
Investigators concluded Brown failed to do a basic welfare check, offer help, or properly report what he saw.
Brown submitted his resignation on April 2 while under investigation, which Police Chief Leo Niemczyk accepted. Internal Affairs formally sustained the violations on June 24th, marking his file as “resigned under investigation.” Two other responding officers were cleared of any wrongdoing.