D.C. homicide detective Ronald Washington shifts nervously as his mind replays the wedding reception last July that turned into a personal nightmare.

"I shot and killed a man," he says slowly, his eyes downcast. "I have problems with it. I dream about it. I have flashbacks. I'm afraid to go back on the street. I'm not sure what I will do. I don't want anyone to kill me.

"People think police officers are animals, that they don't have feelings," he said. "I'm human. I care. Taking someone else's life really bothers me."

While attending a friend's wedding off duty, Washington shot and killed a man who had been threatening other wedding guests with a gun. It was only the second time in his 14 years in the police force that he had fired his gun at someone -- and the exchange of shots left the gunman dead and Washington with a bullet in his back and apparently even deeper scars on his psyche.

Washington went on sick leave after the incident until four weeks ago, when department doctors said he was fit to report for work. He reluctantly returned for seven days, refusing to wear a gun, but found that he was bothered even being around other officers wearing guns. Now he has been put on sick leave again and is trying to retire on disability.

It is rare that a police officer fires a gun except for target practice. Police Chief Burtell M. Jefferson, former police chief Jerry Wilson, assistant chief Maurice Turner and deputy chief Robert Klotz, for instance, have never fired their guns except in practice in their combined 108 years on the force.

In the 12 months ending last Sept. 30, D.C. police officers fired their guns only 58 times on duty and 11 times, including the Washington incident, off duty. In seven of those shooting incidents a police officer was injured, in 13 incidents another person was injured, and in nine incidents, a person was killed by a police officer. In those nine cases, including Washington's, grand juries reviewed the evidence and brought no charges against the officers.

Occasionally officers here, and across the nation, require psychological counseling or suffer nervous breakdowns after shooting experiences. But cases like Washington's are rare, so rare that the D.C. police department has no statistics on the number of officers who have retired because of psychological problems that grew out of a shooting.

That's no consolation though to Washington, a 42-year-old ex-Marine who first learned to use a gun when he was a 15-year-old police cadet.

He constantly relives the shooting in his mind. He avoids the Washington neighborhood where it occurred. He stopped watching police shows on television because he couldn't bear to hear gunfire. If he hears a car backfire, he breaks out in a cold sweat.

Chief Jefferson said he understands how Washington feels. "To be at such a joyous occasion as a wedding and to end up having to fire your service revolver, killing one man and coming close to losing your own life has to be traumatic."

Recently Washington went to talk with assistant police chief Turner about his problems. While waiting in the reception area, he saw the honor roll plaque of District officers slain in the line of duty. There were 24 names on the plaque. He knew 14 of them. At the bottom of the plaque was an empty space where he started seeing his own name.

He dreams about the shootout.He dreams that his gun is in mid-air and keeps firing. He dreams that the bullet that is lodged near his spine is going through his back.

It has been nearly a year since Washington, a photography enthusiast, went to his friend's wedding, shot pictures of the bride and groom, and then moved on to a wedding reception afterward in an apartment building in Northeast Washington.

The night-time festivities, however, were disrupted by an unruly guest.

"I was sitting near the back of the [party] room when I heard a pop," Washington recalled. "I went up front to find out what happened and I saw the groom had been decked. Then a lady behind me began screaming. She had been knocked down."

"I was still trying to find out what was going on when a lady ran into the room and said, 'He's got people in the ball and threatening to kill them.'"

Washington pulled his gun out and hid it behind his thigh. He looked down the hall and saw a man pointing a gun at a security guard.

But Washington hesitated to shoot the man, identified later as Samuel E. McFadden, because a woman, McFadden's mother it turned out, was in the way.

When she moved or was pushed away, Washington ordered McFadden to drop his gun. McFadden turned and fired two shots.

"I knew I was going to get shot," Washington said. "I could have shot him, but the woman was in the way and I didn't want to hurt her. I said to myself, 'This is it.'"

The first shot hit Washington's badge in his breast pocket, ricocheted and sped through his chest near his heart and into his stomach. He spun around and the second shot hit his buttocks as he dropped to one knee.

Washington turned and fired three shots, hitting McFadden in the chest and in the neck.

"The last thing I remember was when I hit the floor I thought I was going to die," he said. "I began praying, asking God to forgive me for my sins."

Washington underwent surgery for seven hours to repair his wounds. His doctors told him he was lucky to be alive: a bullet has passed 1/15th of an inch away from his aorta.

When he woke up, "the first thing he asked me was, 'did I kill the guy,'" said Bernice Henderson, Washington's mother. "I told him, 'yes.' He wanted to know if the guy was married, if he had a family. Then he said, 'I don't know about this job. I don't want to go around killing people.'"

"I told him that he was just doing his job," said Mrs. Henderson, a short, religious woman.

"The whole time I was in the hospital, I was having problems," Washington said. "I kept seeing the shooting over and over again.

"Then it dawned on me -- when I get out of here, I'm going to have to go back to that job. I'm going to have to go back and do it all over again."

When a D.C. police officer shoots and kills a person, he is placed on administrative leave pending a grand jury investigation, but is not given psychological counseling unless he seeks it.

By comparison, officers in the Los Angeles police department are automatically sent to a psychiatrist if they are involved in a shooting incident. In New York City, an officer is sent to a psychological service unit if his supervisor thinks he is have problems, according to James J. Fyfe, a consultant with the Police Foundation.

Former D.C. Police Chief Wilson said the department used to give an officer who had shot someone the day off. "Not as a reward," he said, but so the officer could get himself together. And usually they did.

"It was much more common for the officers who had been shot to be gun shy," said Wilson, who stepped down as chief in 1974. A few officers retired, but most returned to the force.

Four weeks ago, Washington was ordered to report for full duty because doctors at the police and fire clinic said he was mentally and physically fit for police work.

The policeman reluctantly returned, but refused to wear his gun, which police had kept at their property division. For two days, he worked in his old homicide division, reading folders on pending murder cases, but found he became more and more depressed.

He was then transferred to the lineup unit, where he would not have to wear a gun in his job of escorting witnesses to the viewing room.

"It was the human thing to do," said assistant chief Turner. "I thought it would be therapeutic. Maybe in time he could get in a position where he would carry a gun again."

But Washington found he was uncomfortable even being around other officers wearing guns. And in virtually all police jobs, including the administrative ones, police officers wear guns.

Washington went back and talked to the police doctors, and after seven days on the job was placed on sick leave again. Police officials won't disclose the doctors' reports, saying the information is confidential.

The policeman's own private psychologist, Dr. James Ballard, says Washington is "emotionally unfit" for police work. "Mr. Washington has undergone a great deal of trauma. To put him back to work would only further traumatize him. He is depressed. His reaction time is slowed . . . Only this guy's personal fortitude has prevented him from crumbling into a heap."

"I don't see how anyone can consider this man a malingerer," Ballard added. "To think that this guy could pick up a weapon and continue precludes human nature."

Some of Washington's colleagues offered him suggestions on how he could overcome his fears.

"One officer told me to just remember that the guy I killed was a SOB and no good. Then take a couple of drinks and forget it."

"I don't drink," he said, shaking his head in disbelief at the suggestion.

Someone else suggested that he only needed to return to the streets to regain his self-confidence.

"I know the streets," he said. "You can't be taking extra time to think. You have to act sometimes in a matter of seconds. I'm not that alert. Things happen fast. You got to react quick, I don't want to hurt anybody else."

Washington's mother said she also would fear for his life if he returned. "I feel if he had to shoot again, he will hesitate. It would mean his life. I'm afraid for his life if he stays on."

Why doesn't he quit?

"I just can't quit," Washington says. "I have given 14 years to the police department.For me to quit now, what would I do? I just don't feel like throwing all away. I did my job. I did what I was trained to do. I got hurt doing it."