While riding his police scooter, Officer Anthony (Bud) Mazzant was sideswiped by a car and went sprawling. He bounced and rolled along the pavement and came up with a face covered in blood. "I thought he was dying," his partner later testified.

Mazzant, 27, suffered a concussion, cracked teeth and a wrenched back. He went on sick leave for 18 months, claiming he could not return to work because he suffers from headaches and backaches.

Recently, a District of Columbia police trial board, presented with candid camera-type films of Mazzant bowling and waxing his car, fired him for malingering.

"I'm done," Mazzant says now. "Bill collectors are after me. The doctors told me I could exercise until I felt pain and that's what I did . . . Now what am I going to do?"

Mazzant's case is significant beyond his personal plight because it is a measure of a toughening attitude within the department toward young officers headed for disability retirement.

Four officers have been fired for malingering in the last five months, and two others have resigned rather than face a trial board.

Investigators told the trial boards they caught Mazzant bowling four games and waxing his car "vigorously, with both arms." They found Officer James W. Kegney (bad knee) working on a cnstruction crew while awaiting an appearance before the retirement board, Sgt. Haywood Moss (bad back) lifting an attache case and walking without the cane he allegedly claimed he needed, and Officer Denise Wilson (bad leg, whiplash) climbing into and out of her car "in a normal manner without any evidence on abnormality."

All the officers acknowledged their activities but claimed that the intentity of their pain, or disabling condition, varied from time to time.

"We're cracking down on these extended sick leave people," said one police department official. "It's something we should have done years ago."

Until recently there never had been police officer fired for malingering, an ugly word in an image-conscious department.

The attack on the sick list is being led by the casualty investigation unit, on team of 12 internal affairs officers who spend most of their time stalking inspected malingerers to see if their behavior is consistent with their invary.

All have appealed their trial board convictions to Mayor Walter E. Washington. He has turned down Kegley's request, and is expected to decide the others by the end of next month, according to a spokesman.

An examination of the department's saw tactic also reveals much about the sick list and disability retirement system here, including:

The difficulty in determining who is sick or injured enough to retire and who is not.

The tendency of police doctors, faced with inconlusive evidence, to recommend disability.

The difficulties facing the retirement board in rejecting such a recommendation.

The department's crackdown is spurred in part by the uncommonly high (92 percent) ratio of retired officers who have gone out on disability, which means their pensions are tax-free.

This system has drawn fire from Congress, particularly after recent publicity about high ranking police officials retiring on disability. Legislation has been proposed to tighten up existing laws.

Some department officials contend that the real abusers of the system are not the senior officials who go out with degenerating health after decades of service, but officers in their 20s and 30s "who are looking for that pie in the sky," as one retirement board member puts it.

These officials reason that the older men would be retiring anyway and thus would still draw a pension from the city. The younger men not only draw pensions, but force the city to hire a replacement.

All those fired recently are under 40 years old. The average age of officers retiring on disability last year was 38, with 14 years of service. It takes at least 20 years of service for regular retirement.

As a result of the new pressure many of the estimated 75 men now on extended sick leave (out for more than three months) are virtually prisoners in their homes.

"I stay inside as much as I can," said one bitter officer. "If step outside they'll roll the cameras and try to trump up a case on me."

Many of these men claim serious injuries, and are frustrated by the length of time, months and sometimes years - it takes them to get an appearance before the Police and Firemen's Retirement and Relief Board.

For their part, the police doctors claim that they cannot find much wrong with some of the patients.

Mazzant was one, according to the police doctors.

"It is almost like having a headache. He is the one who knows whether he has pain or not," Dr. Eugene Short testified at Mazzant's trial board. ". . . So whether he could bowl or wax his car, he knows how much pain he is having and how much limitation."

Mazzant testified: "the pain was constant'y there. There was no relief from that. It was just that on some days it was worse than others." Doctors recommended he exercise, he testified, and he quit when the pain became unbearable.

Mazzant's colleagues and superiors testified that he was an excellent officer, not prone to complaining.

Short said that the police doctors believed Mazzant could do light duty, but that he felt he could not. Mazzant introduced statements from independent consultants that, while sometimes contradictory, contended he did indeed have a traumatic back injury and could not resume police work.

The police doctors, despite their belief that Mazzant could do light duty, eventually recommended that he was permanently disabled and should be retired.

"With these type cases it's a question of whether we wear them out first or they wear us out," said one police physician, who asked not to be named. When doctors are skeptical about a patient's injury, they can send him to a series of consultants or bury the paperwork, the doctor said, " but there comes a point in time that if the patient refuses surgery and says he cannot work, we have no other alternative than to send him to the retirement board."

More often than not police doctors ultimately recommend to the board that the patient is "permanently disabled," because they fear a possible malpractice suit, or that they will be tied up in court on an appeal of their decision, according to some police physicians.

These recommendations of permanent disability contribute significantly to the high percentage of disability retirements here.

Once police physicians make such a recommendation, courts have ruled that the retirment board must grant disability retirement unless it can prove that the officer is not disabled.

Board members claim that this is almost impossible, considering the vague and sometimes conflicting medical testimony submitted on behalf of applicants. Last year of 101 officers who appeared before the board seeking disability retirements, 96 received them.

In virtually no other retirement system, according to senior city officials, is there a layer of administration that recommends disability retirement. In other systems, including the federal ones, the burden of proof of disability rests with the applicant.

The outside consultants used by police physicians are often vague in their reports and are of little help in determining a man's fitness for duty, or for retirement, according to police doctors and retirement board members.

Some board members were incredulous recently when they read a newspaper report quoting Dr. Stanford Lavine, an orthopedic specialist, as saying that a possible disk operation on basketball player Phil Chenier was not serious.

"He has told us the same kind of injury is permanently disabling," one board member said. "How can we retire people on disability wnen basketball and football players have the same injuries and wind up playing again?"

Lavine will not comment on the matter, according to one of his staff members.

An orthopedic specialist who teaches at Johns Hopkins University School of Medicine said yesterday he regards any disk surgery as serious because of the potential for complications.

He said that recovery from back injuries is closely linked to motivation, and added that medical studies have shown that people with back problems seem to do less well if litigation is involved. The specialist, who was consulted by The Post, asked not to be named for fear it would appear he was seeking publicity.