A Welfare Check Turned Into A Murder Investigation After A Phone Call Abruptly Ended

In December 2016, Michael Agerter was talking to his sister on the phone when she heard three loud booms then silence.

Michael Agerter, seen here smiling with his dog, was murdered in December 2016.

In December 2016, Michael Agerter was talking to his sister on the phone when she heard three loud booms then silence.

Photo by: Warner Bros. Discovery, Inc. (Screenshot from ID's "The Murder Tapes")

Warner Bros. Discovery, Inc. (Screenshot from ID's "The Murder Tapes")

Nine days before Christmas in 2016, 31-year-old Michael Agerter was on the phone with his sister as he pulled into the driveway at his Maricopa, Arizona, home and eased his car into the garage.

He put the vehicle in park, and was working on shifting his phone conversation from the car speaker back to the phone when his sister heard three loud booms and then a sickening silence.

His family, who lived in Ohio, contacted the Maricopa County Sheriff’s Office to do a welfare check at his home. When a deputy arrived at the home, he found neighbors standing on the sidewalk across the street staring intently at the home.

According to the neighbors, a white van had driven into the subdivision and they then heard three gunshots.

Agerter’s garage door was still open, and the deputy noted a series of bullet holes through the back driver’s side window. The man was slumped in the front seat with an obvious gunshot wound to the head. The deputy radioed for emergency medical assistance, but it was too late. The firefighters who arrived at the scene confirmed that the man was dead.

“Premeditated, Personal, and Extremely Cold-Hearted”

Officers cleared Agerter’s home, wondering if they would find a suspect hiding inside, but nobody was there.

As investigators began to process the scene, they found three spent shell casings on the garage floor near the car and a shoe print in the mud between Agerter’s house and the home next door. Traffic cops in the area initiated stops on white vans on nearby roadways to see if they would happen upon their killer.

Because the car was still running and Agerter still had his sunglasses on, investigators believed he had been ambushed just as he arrived home. Further examination of the body revealed that beyond the obvious gunshot to the head, he’d been hit in the neck and upper body too. Officers who worked the scene described it as “gory” and believed that the crime and its motivation was “premeditated, personal, and extremely cold-hearted.”

As authorities began looking for possible suspects, they found records of an order of protection that Agerter had against an ex-girlfriend, Kathryn Sinkevitch. Agerter was reportedly a victim of domestic violence at the hands of Sinkevitch, and he had severed their relationship and filed for the order of protection after she allegedly got violent in the apartment they used to share.

After Agerter moved to his new home, somebody tried to burn the place down by using a torch on the garage door and front door. The plot was unsuccessful, though it left extensive burn marks on the house. While authorities couldn’t ever prove Sinkevitch was responsible for that crime, Agerter had installed surveillance cameras before his murder.

Had the surveillance captured footage of the killer? Get the details on the season premiere of The Murder Tapes July 6 at 9/8c on ID. Previous episodes are available now on discovery+.

If you or someone you know is dealing with domestic violence or abuse from a romantic partner, you can visit the National Domestic Violence Hotline website, call 1.800.799.SAFE, or text START to 88788 for help. Advocates are available 24/7 to help callers talk through their situation and connect them with local resources. There is no charge to reach out to the National Domestic Violence Hotline.

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