LOS ANGELES, Apr. 28 – For the last 25 years, Lt. Bob Helder has worked for the Los Angeles Police Department; claiming no other credit than “being a good cop.”

He has had to be. Helder occupies what some say is the most sensitive, difficult job on the force: supervisor of the Officer-Involved-Shootings Section. No matter what Helder does, he is open for criticism — from members of the department and from the public.

Every time an officer fires his weapon, it is Helder who oversees the ensuing investigation. On the facts he uncovers, the man — and thereby the department — are absolved. Or both are besmirched.

In either case, Helder is the man to whom the responsibility has fallen, for washing publicly the department’s linen. Since 1967, Helder has supervised this section, vowing straight-faced not to take it home with him.

In their Sherman Oaks home, Helder never speaks of police business to his wife, Ann, but he keeps a notebook at bedside. It may seem that he has effectively locked “the job” away in a corner of his mind when suddenly he sits up and jots an idea that would otherwise be long gone by morning.

Often, that note turns out to be the elusive answer Helder has sought.

When Helder, 48, retires in May his note-writing and painstaking attention to detail won’t be useless habits — he will become a private investigator, joining two other former law enforcement officers.

Those who will miss him the most are the police officers, who respect him for his integrity and unbending ethics; and newsmen, who have learned to expect straightforward answers and honesty at all times.

Both have found Helder at the center of controversy for about a decade. Before it was split administratively, the Homicide Special Investigation Section was under his purview. To it fell the task of investigating the Charles Manson Family, the Tate-LaBianca murders and the assassination of Robert Kennedy.

But to the public who reads stirring accounts of running gun battles and mass murder, Helder’s is the forgettable name to which newsmen attribute their information. He has never been the reason for news but the source of verification.

What helps to explain how Helder achieved such respect is found in his philosophy.

“I’ve never found it too difficult to be impartial because all you’re doing is reporting facts and you have to let the chips fall where they may,” Helder said.

“The job has been good to me and I’ve been good to the job. When an officer makes a mistake, though, I take it as kind of a personal thing.

“I’ve spent most of my adult life being a policeman and I’m proud of it. That’s the thing about being a policeman: if you screw up, then every officer on the force has to take a lump for you.”

With no special physical traits, Helder is as inconspicuous as a window shopper. He seems to have no talent for deception. Wearing his emotions on his shirtsleeve, Helder is easy to understand.

Helder has a reputation for fairness and kindness that can only match his capacious memory. He has the kind of personality that is light, resilient and enduring. That, coupled with a good sense of humor, has helped to keep his balance over the years.

“If you don’t have a sense of humor, you’ll wind up in the booby hatch,” he laughed. “You see so much blood and guts in this job that you just can’t afford to take it home with you and talk about it. If you do, it’ll destroy you. Even so, there’s still something always going on in the back of your mind.”

Investigating the Tate-LaBianca murders in 1968, Helder filled four notebooks alongside his bed. But it wasn’t until Susan Atkins, one of the “Family” members, was picked up on a separate murder case that the entire story began to come to light.

“When Susan Atkins laid the whole story on us — Bang! That was it. But for three months before that, it was nothing but dead end after dead end.”

During the course of the investigation, Helder was badly shaken when a piece of information most newsmen had agreed to keep silent leaked to a suburban newspaper. After the Tate murder, police had found a pair of prescription eyeglasses on the grounds. To this day, ownership of the glasses has never been explained.

“When I first got on it, I was getting calls from reporters all over town and I asked them to keep it quiet and give us a chance to run it down. So they all agreed to sit on it,” said Helder.

In the days that followed, he distributed circulars to optometrists and ophthalmologists all over the state in hopes whoever owned the glasses would seek replacement. By chance, a young reporter, who went to his eye doctor for new glasses, saw the circular on the doctor’s desk.

“The next thing I knew every reporter thought I had sold him out and I was on national television the next day trying to explain what happened,” Helder said.

“That hurt because I’ve always had a good working relationship with reporters. When I’ve asked them not to print something during an investigation, they’ll cooperate.”

Following the Tate-LaBianca case, Helder’s interest in the professionalism of his work caused him to become actively involved in a group of law enforcement officers which founded the California Homicide Investigators Assn. Helder was elected first president.

Now with more than 400 members, the group meets for a two-day conference each year, occasionally featuring speakers from the news media.

“We’ve had speakers from the media to help us straighten out this flow of information from the department to the papers?” Helder said. “I’ve always figured it was healthy to kick around new ideas. We’re not always going to come out looking good. But hell, if there’s a controversy, then I want to see both sides.”

For all the aplomb Helder has shown fielding questions under pressure, he comes off as shy over the attention he’s receiving for completing 25 years of service on the force — all in one piece. No bullet wounds. No knife scars. He’s been lucky, he says, but he’s a pro.

By JEFFEREY HANSEN