On his first day on the job, 50 years ago, Tom Jacocks was handed a .38-caliber Colt revolver and a ticket book and was told to get to work.

His beat: Bethesda.

His other equipment: a 1954 Chevrolet with a police radio. And a uniform. That was it.

Today, "things are a lot more complicated," Jacocks said in an interview in his spartan office in the Bethesda police station, where he is a lieutenant and deputy commander. "You have a lot more things to work with. We didn't have Tasers in 1955; we didn't have breathalyzers. There certainly was no such thing as DNA."

When officers prepare for patrols, Jacocks sees them load up with all manner of technology: laptop computers, cell phones, Tasers, slide-action Glock handguns.

Tomorrow, Jacocks will celebrate his 50th anniversary as a Montgomery County police officer. It is a record for longevity in Maryland; nationwide, he is among the officers who have served longest with a single department.

"It's truly remarkable," said Capt. Betsy Davis, who was Jacocks's commanding officer for two years. "What's even more remarkable is that he's not just sitting somewhere where the department has hidden him. He's a deputy commander, which is not an easy job."

Jacocks, 72, still regularly writes traffic tickets -- sometimes more than are written by beat officers, Davis said -- and is on call, showing up at crime scenes at night. He keeps the police radio switched on in his office and often hits the street for calls.

"He is a cop's cop," Davis said.

Jacocks applied to be a Montgomery police officer in the fall of 1954 but waited nine months before getting a call back.

"The chiefs at the time were apparently not that impressed by me," Jacocks said with a bit of a smile.

They called him in June 1955. He took an entrance exam, which he remembers passing with a grade of 97 percent, and showed up at the Bethesda station.

"They handed me a gun and told me to get to work," he said. It was 4 p.m. on Friday, July 1. Dwight D. Eisenhower was president, and the county's population was about 200,000.

Jacocks had recently finished a two-year stint with the Army. As an officer, he quickly gained a reputation as being quiet, solid and knowledgeable, said Montgomery Sheriff Raymond M. Kight, who was sworn in as a Montgomery police officer in 1962 and worked for the department until 1967, when he became a sheriff's deputy.

There was nothing flashy about Jacocks, as the officer himself is the first to say.

"I haven't been involved in anything really spectacular, but I've been involved in a lot of things," he said.

Bethesda has changed dramatically since Jacocks started there. The department had about 180 officers at the time; it now has an authorized force of 1,111. When Jacocks began his police career, on a typical night there might have been three cars on patrol in the county. Now there are at least that many on an average night in Bethesda and five or six times that number countywide.

The county's population was about one-fifth of the estimated 2005 count of 942,000. The tallest building in Bethesda had three floors.

"It was almost what you would call a quiet country town," Jacocks said.

Jacocks lives in Kensington, not far from the Bethesda house where he grew up. Except for his stint in the Army, which took him to Fort Leonard Wood in Missouri, he has spent his life in Montgomery County.

"He hasn't changed in 50 years," Kight said. "He was very quiet, very knowledgeable. You could ask him anything about the law and he'd have an answer."

Jacocks speaks in short declarative sentences. Just the facts. When he relates a humorous story, a bit of a smile creeps across his face, but nothing more. Not exactly taciturn and not really tight-lipped, he is more of a minimalist with words.

The philosophy is reflected in his office, which has just one item on a wall: a Norman Rockwell painting that, he says, someone else put there.

In a pair of interviews over a week, he demurred on several questions about his family and his life outside of work, saying: "This isn't a soap opera. It's about me and 50 years with the department."

Indeed.

The department has planned a celebration for today for Jacocks, who made clear that it is not a retirement party: "I have no date set for retirement," he said. "Everybody's asking when I'll retire, but I'll make up my own mind on that."

As for the celebration: "I'll be there," he said. "Attendance is not optional."

Tom Jacocks while on patrol in Silver Spring in 1982. Jacocks, a deputy commander, will celebrate a half-century on the county force tomorrow.When Jacocks started as an officer in 1955, his radio was among his few policing tools. Now "you have a lot more things to work with," he said. "We didn't have Tasers in 1955; we didn't have breathalyzers. There certainly was no such thing as DNA." He still regularly writes tickets and goes to crime scenes.Tom Jacocks holds a photo from 1959. "I haven't been involved in anything really spectacular, but I've been involved in a lot of things," he said.