He arrested the man. But that alleged crime may be only the beginning of his legal troubles. Police believe the man has connections to at least two unsolved murders.
Patrick Martin has been in jail since September since that armed robbery. But it appears he knows law enforcement agencies have him linked to other crimes.
On June 6, 2003, Katherine Feltson's only child, Felix, was shot and killed on Saginaw's east side.
"It was like a drive-by, some guys with some masks," she said.
Nearly seven years later, there have been no arrests. But in recent weeks, Katherine Feltson has hope.
She says a Michigan State Police detective told her there is a person of interest in the investigation. The name she was given?
"Patrick Martin," she said, "and it was like I was blown away."
Michigan State Police confirm Martin is a person of interest in the Feltson murder case.
Martin is on trial this week, accused of robbing a Saginaw 7-Eleven. Feltson says her son and his wife have two children, and she says her daughter-in-law also has two children with Martin.
"If he did this to my son, I need him to confess so I can have some peace," she said.
In this month's issue of Mugshot Magazine, Felix Feltson is featured with other unsolved murder victims. Pictured next to him is Debra Kukla, who was found murdered in her Bay City home last June.
Bay City police confirm Martin lived with Kukla, and that Martin discovered her body and made the call to 911.
Police also confirm he has been questioned with regard to the case. Once again, there have been no arrests, but according to his attorney, Martin knows a murder charge in at least one case is possible.
With an armed robbery conviction, Martin faces life in prison.