Phoenix police announced one of its officers is suspected of sexually abusing his sister, albeit when he was a teen.

In March, a 17-year-old girl told police her half-brother, Michael Mason, 28, committed sexual conduct with a minor when he was 16 and she was in kindergarten.

Police estimate the crime occurred 12 years ago.

Investigators developed probable cause to arrest Mr. Mason, who had been employed as a Phoenix officer for about three years. He was first a civilian employee, as he was hired in 2011.

He resigned prior to being booked into jail.

“I am shocked and appalled to hear the details of this investigation,” Phoenix police Chief Jeri Williams stated. “I am confident in the investigative process, as well as the current stringent hiring and background investigation process under my watch as Police Chief. It is incumbent upon our organization to review these processes to ensure we are making every effort to detect and address these types of incidents.”

Mr. Mason was booked into jail on one count of sexual conduct with a minor. His bond was set at $35,000.