YORK, Maine — While policing has changed dramatically since he became a cop 41 years ago, York police Sgt. Gary Finley said the core relationship between him and the public he serves really isn’t much different now than it ever was.

“I’ve always had really good luck with people. They are the same whether they have nothing or whether they have a lot. You treat them decently — that’s the key,” he said.

It’s an approach that has always worked for him — not only in his job as a patrol sergeant for York but as the owner of D&F Classics used car dealership in Eliot, which he has run for 25 years while working full time for the York police.

“I’ve arrested people over the years who still buy cars from me,” Finley said Thursday, his last day as a full-time officer. He will officially retire March 1 after 35 years with the York police force.

Over the years, he’s counseled grieving family members who have lost a loved one, talked down drunks or people high on drugs, and more than once, given money out of his own pocket to help someone out. For instance, there was the woman whose sons are well-known to York police, young men Finley called “good kids, just misguided.” One of her sons had been arrested and she came to the station to get him but did not have the $100 for bail. Finley gave her the money and told her to pay him back when she could.

“People thought I was nuts, but she paid me back in a couple of days,” he said with a shrug.

Finley said over the years he stopped a lot of cars for traffic offenses but most often has given out warnings — enough so drivers are aware of the ramifications of doing something wrong, but at the same time giving them a break.

One of those drivers was Detective Owen Davis. When he was a teenager, he was given a warning after being stopped by Finley “right on Ridge Road by the post office. You don’t forget something like that,” he said with a laugh. “At least I didn’t.”

Finley said he’s gone into many bars over the years to quell fights or to serve warrants — recalling a time when the beach had rowdy places such as the Sand Dollar or the Draft House on Ridge Road.

“They’d tell me I shouldn’t go in there by myself,” he said, “but I knew these people. And they knew I’d treated them decently.”

Perhaps not surprisingly, he taught community police at the Maine Criminal Justice Academy for a number of years. And as a supervisor of full- and part-time officers, he’s told them it’s best to live by the golden rule. One of the many accolades he’s received since his retirement was announced was from a police chief in a Massachusetts town who thanked Finley for mentoring him when he was “still wet behind the ears” as a summer officer.

In fact, as of Thursday morning, more than 12,000 people had viewed the York Police Department Facebook page write-up about Finley’s retirement.

Police Chief Douglas Bracy calls Finley the department’s “ambassador.”

“Part of being in a small community police department is being part of the community, and Gary has always been there whether on duty or off. He’s the first guy to serve the needs of the underprivileged in our community,” Bracy said. “This is a hard loss. He’s been an exemplary member of our department.”

It’s a job Finley said he’ll miss.

“I’ve been really happy to be a police officer. I think when I was new and the job was so exciting, I’d almost do it for free,” he said.

A celebration for Finley is being held 6-9 p.m. April 16 at the Union Bluff Meeting House in York Beach. The price per person is $25, which covers hors d’oeuvres and a contribution toward a gift.