The suspect, Christopher Lynn or Warren, was allegedly posing as an officer to teens attending Hazel Park High School, police say.
Lynn was arrested on Tuesday.
"He looks scary," said Jessica Miner. "I wouldn't want him around my kids. I wouldn't want my kids to run into him."
Miner, a high school parent, says she's disgusted to learn that Lynn, 30, was accused of approaching teens at the school.
"This individual identified himself verbally as being a undercover police officer working narcotics," said Chief Martin Barner.
On at least two occasions police say Lynn approached three teens asking them if they use drugs or know other students who do.
He also allegedly attempted physical contact with one of the teens.
"The first individual he approached, he asked him if could pat him down," Barner said.
The teens alerted their parents. Police alerted the school. Students recognized his photo and his bright neck tattoo immediately.
"I've seen him walking up the street," one male student said.
"He was too shady to talk to," said another student.
The three teens tell police that when Lynn approached them, something seemed a little off. They noticed his clothing and his mannerisms.
One teen even asked Lynn if he was a real police officer.
"He told them, 'You don't think I'm a cop,'" Barner said. "'You want to see my credentials.'"
Lynn is charged with one count of impersonating a police officer. He told police the reason he was doing it is because he enjoys police television shows and "has always wanted to say things like like that."
"Even though what he indicated as his reason for doing this, you don't really believe that too much," Barner said.
Police are asking that any other teens Lynn may have approached, come forward.