Sheriff Michael McCormack sits with his six-foot-four frame wedged into a cramped office just inside the front door of the Edgartown house of correction. He is reminiscing about some of the pictures on the wall and some of the people who influenced his long career in public safety.

He has lots of people to thank as he finishes his last term as the elected sheriff of Dukes County and eases into retirement at the age of 69. He settled on the decision to hang up the keys to the jail earlier this year.

“When I ran the last time it was in the back of my mind,” he said. “It had nothing to do with whether or not I like the job, I still love the job.”

Martha’s Vineyard voters elected Sheriff McCormack to a six-year term in 1998, reelected him in 2004 and again in 2010.

Jail was built in 1873, when Ulysses S. Grant was president. — Michael McCormack

He moved to the Island soon after leaving the Marine Corps, and took a job as an Oak Bluffs police officer.

“My mother was born here, I spent summers here,” he said. “I knew this was the place I wanted to raise a family.”

In 1972, he began working at the county jail part time. A year later he was named special sheriff. When he first took that position, the job required living at the Upper Main street jail. It was a package deal. His wife prepared meals for the inmates. The couple also began raising their three children while living at the residence in the building.

The number of people incarcerated has increased dramatically since Sheriff McCormack began his career. The jail and house of correction can now accommodate up to 35 people, though it’s rarely that crowded except on the occasional summer holiday weekend. The sheriff also manages the 911 emergency communications center and the community corrections center, both located near the Martha’s Vineyard Airport.

His policies have always leaned heavily toward the rehabilitation side of the corrections equation. He said inmates stay an average of nine months in his jail. “I firmly believe that punishment takes place at 81 Main street, the courthouse,” he said. “Once a person walks in this door here, we try to work with them for the day they’re eventually released. From day one we start trying to identify what the issues are in their life, and try to set them up with programming that addresses those issues.”

One of 14 county sheriffs in the state, Sheriff McCormack has established programs for education, substance abuse counseling and life skills for inmates who want to work at rehabilitation.

“The people who end up here serving time aren’t necessarily bad people,” he said. “But they’ve made bad decisions. It has to be all about rehabilitation. If we don’t try to help, they’re just going to come back. We do hold people accountable if they don’t follow the rules, but it’s not about punishment. It’s about helping people who have hit rock bottom. People who wind up in jail, that’s the bottom.”

Those policies have brought some criticism, including of a policy that allows inmates to be transferred to the Dukes County jail from other facilities. Transfers can only occur with the consent of the sheriff.

He defends the policy. “We’re not just a small jail sitting on an Island, we’re part of a larger correctional system,” the sheriff said. He said a transfer might be arranged, “if somebody is in a situation where they’re not safe, because of the type of crime, possibly, they’ve committed, they can’t be put into the general population, or the type of individual they are, they are subject to being preyed upon. We do that also if someone is incarcerated in another facility that has ties to the Island, family ties, because family is one of those other keys to success.”

Sheriff McCormack takes the criticism in stride.

“I got elected three times. The community had to agree with me on some level,” he said. “I’m not here to please everybody, I’m here to do the right thing. Every time I accept somebody under those conditions, I know I’m doing the right thing.”

A portrait of General Ulysses S. Grant behind his desk serves as a reminder that the jail was built in 1873.

“He was President of the United States when this jail was built,” Mr. McCormack said. The sheriff said he has had few disappointments after more than four decades on the job, but one of them is falling short in a quest to replace the aging facility that sits at the head of Main street in Edgartown.

“It was designed under a different correctional philosophy. It was designed to separate inmates from each other, more of a punishment model,” he said. “The newer facilities are designed totally different.”

There were studies and an initial plan to construct a new jail near the airport, but the project never gained public support.

“I certainly understand, because of the number of inmates, a large investment in a new facility probably wasn’t feasible,” he said. “Hopefully it will be in the future.”

But it won’t be on his watch.

Sheriff McCormack said when he leaves in January 2017, he will miss most aspects of his job, including the department staff, inmate rehabilitation programs, and even the commute from his West Tisbury home.

One thing he won’t miss is the number of familiar faces he sees returning to serve sentences.

“I’m not going to miss the failures, some of the people you try to help, and they continue to come back,” he said.

Comfortable in a sweater and blue blazer, Sheriff McCormack gazed around the tiny office. A series of photographs depicts how the jail has expanded over the years. Others show the jail prior to 1873, which was located on the lawn of the Edgartown courthouse, where the war monuments now sit.

There are also pictures of people who helped and influenced him along the way. He mentions his predecessor and uncle, the late sheriff Christopher (Huck) Look Jr., the late Oak Bluffs police chief Peter Williamson, and former Edgartown district court clerk-magistrate Thomas Teller.

Sheriff McCormack said he looks forward to traveling, reading and visiting his new grandchild after he retires. He said he hasn’t been able to spend as much time with his family as he wished during his public service career.

“Now I’m going to have that opportunity,” he said. “Forty-four years is a long time. It’s been my life.”