The Associated Press reported on Monday that Mr. McCarthy was charged with more than 20 crimes in New Hampshire between 1997 and 2011. A warrant for his arrest was issued there in 2013 when he failed to show up for sentencing after he was convicted of disorderly conduct, The A.P. said.

Sergeant Lowe said there was also a warrant out for Mr. McCarthy’s arrest in Johnson County, Mo. Court records show that he was charged with unlawful possession of a firearm there in 2015.

Officer Michael was a lifelong resident of Clinton, Sergeant Lowe said. He is survived by his wife and two stepsons and had been on the police force for less than a year.

“He had a past military background and his desire was to be a police officer,” Sergeant Lowe said. “It just came to the point where he was able to do that.”

Before shots were fired, Officer Michael radioed in a description of Mr. McCarthy’s car, a 2008 Dodge Nitro sport utility vehicle, according to a probable cause statement filed with court by Sgt. Greg Martin, an investigator with the Highway Patrol’s Division of Drug and Crime Control. He said the vehicle was registered in the suspect’s name.