Correction Appended

Capt. Daniel Madigan lives in two worlds: one overseas in the midst of war and one on Capitol Hill beside Members and staffers.

He has traveled the world, parachuted from planes, analyzed intelligence and seen the face of terrorism since he enlisted in the military in 1988. But for the months and years in between, Madigan has returned to a civilian job.

And since 2003, that job has been serving as a sergeant with the Capitol Police.

Madigan has handled that transition several times. He isn’t the only one: At least 80 Capitol Police officers are enlisted in the reserves and many more are veterans, according to the department.

Enlisted officers say they keep up their dual lives because they love the excitement and pride of their military jobs. But the choice also comes with sacrifices: Children grow up, jobs change, friends move. Madigan missed his daughter’s birthday three years in a row and was overjoyed when he was finally able to join in the celebration this year.

“In the seven to 10 months when you’re gone, things can change. At least to me they do,” said Madigan, an intelligence officer in the Air National Guard. “There is an adjustment coming back. I’m sure the adjustment for everyone is a little different.”

Capitol Police officials recruit from military bases and colleges, attracting military officers who have learned discipline and skills that are helpful in a federal law enforcement agency.

Madigan praised the department for seeing “the big picture” and realizing that the time officers spend away in the military actually helps strengthen the police force in the long run.

“Many employers will see an officer going away from the negative perspective,” he said. “Here, my experience has been the opposite. They see the bigger picture, that you’re doing something very similar to what your position is here.”

Still, enlisted officers face hardships even in supportive departments. While they’re gone for six, 10 or 18 months, they miss new training requirements and work opportunities.

Until recently, they’ve also missed their salaries. When deployed, they are taken off the department’s payroll and put on the military’s — a change that can mean a significant cut for some.

That changed when Congress recently passed a bill requiring federal employers to make up the difference between an employee’s military salary and government salary.

But there are still kinks: Officer Andrew Ricken said the department’s policy is to follow the letter of the law by counting entitlements (such as hazard pay) into its calculation for the military salary. But some of his military colleagues, he said, get better deals from state police departments and other federal law enforcement agencies.

Still, Ricken, who has been in the military for 13 years, said he is dedicated to continuing to serve. His interest began in his childhood, he said, when his grandfather would tell him stories about World War II. He has chosen a dangerous specialty: He is the crew chief on a Black Hawk helicopter, in charge of weapons and passengers as his team transports troops and equipment.

Ricken just got back from an 18-month deployment on Jan. 21. The adjustment was stark, he said: He went from being in the middle of a war zone to guarding Members and tourists as a Capitol Police officer.

“It was a little rough at the beginning because you get so used to the adrenaline rush,” he said. “You get home and the adrenaline rush is no longer there, and you get looking for what’s missing. There can be slight depression.”

For some officers, the depression can turn into post-traumatic stress disorder — a condition that can be especially difficult to handle when returning to civilian life as a police officer, a job that can be unpredictable and stressful.

But enlisted officers and military veterans say they share an instant bond on the force and come to each other’s aid. Earlier this year, Officer Jim Davis, an Army veteran, held a golf tournament to raise money for the family of a fellow officer who committed suicide after returning from his third deployment.

Officers described the transition after deployment as a series of stresses and changes, some seemingly minor. Sometimes, they said, the difficulty is just in the change of environment. Davis remembered entering the Capitol Police after almost 10 years of active duty in the Marine Corps and the Army (he is currently in the Army Reserves). The “rigidity” of the military, he said, contrasted sharply with the structure of the police force.

He learned the difference during a State of the Union speech by then-President Bill Clinton. A superior told him to hold his hands on a door and not let anyone through. He took it literally — and engaged in a struggle over the doorknob with the Minority Whip, who was trying to get through the door to see the speech. Davis didn’t recognize him and was trained to take orders to heart.

“I kind of learned my lesson,” he said with a laugh. “Obviously, you got to take things in context.”

Ricken also said he has learned to change his manner — he can’t order Members and staffers around like he does when protecting passengers on a Black Hawk helicopter.

Sgt. Tony Buffington said he almost quit when he joined the Capitol Police because of the shock of the change. He has served in the Marine Corps, stationed at Guantánamo Bay, Cuba. The Marines, he said, “completely tear you down in boot camp until you’re nothing, and then they build you up until you’re king of the world.”

That, of course, isn’t the case in a police department. “It was a little rough for me because they didn’t have the same discipline,” he said. “But you can’t expect every job in the civilian world to have the same discipline as the Marine Corps.”

But the two jobs can also work hand in hand. Madigan said he learns skills that translate easily on a police force tasked with protecting a terrorist target.

“For me, I found that a lot of the skills and knowledge that I obtained over the years working with the intelligence community — with a new focus on counterterrorism, especially in this agency — it helps me look at it through a different prism, with a different perspective,” he said.

Correction: May 24, 2010

The article incorrectly identified the rank of Tony Buffington, who is a Capitol Police sergeant.