THEY USED TO ARRIVE in large manila envelopes with the name of the doctor printed in the corner, and sometimes I would get to look at one of them, hold it to the light and try to see the pain. It would be an X-ray, usually an X-ray of a back, and usually it was submitted by someone who swore, in court and elsewhere, that his pain was more than anyone could take. The cure, of course, was always money.

It was hard to prove anything one way or the other. One of things you learned right off in the insurance business was that you cannot X-ray pain - prove beyond a shadow of a doubt that someone was or was not in pain. You could look at the X-rays and read the reports and make your guesses, but the only time you ever proved anything was when you caught someone forgetting his act and putting aside his crutches for something like a game of football.

But that, in truth, almost never happened. What did happen was that a whole industry developed around personal injury claims - doctors and lawyers and other specialists, all of them playing with the truth, all of them sort of daring you to prove otherwise. It was hard to do anything about the situation, and after a while some people came to view an automobile accident as something other than a tragedy - a financial opportunity, for instance.

You get somewhat the same feeling about Washington's disability retirement program for police and firemen. You get the feeling that everyone knows it's a fraud, that something ought to be done but that everyone has come to accept it as a more or less honest way of making money. It has come to be seen as a bit of a bonus tagged on to the retirement program, a little extra in tax-free dollars that you get simply for going through some bureaucratic motions. You can say your back hurts, and since no one can prove otherwise, you walk away with the money.

The latest applicant for disability retirement is Burton W. Johnson, the city's fire chief. He follows by about a month the city's police chief, Maurice Cullinane, who, at the age of 45, succumbed to the rigors of a desk job and packed it in. Since then, cynics have showered job offers on the man.

Now we have the case of Johnson, for 35 years a fireman and since 1973 the chief of all the department and a man of 60 with a back problem. He is saying, according to the newspapers, that he is putting in for disability retirement, and he is saying further, according to people who speak for him, that no matter what, he is going to retire. He is, after all, 60 years old. There is a commendable honesty at work here, Johnson being the first high police or fire official to indicate he views disability retirement as nothing more than a super pension. If you can get it, fine: if not, you go anyway.

There is no point singling out Johnson. He is only following tradition, going along with the system. Of the approximately 1,000 former Washington firemen currently receiving a pension, about 83 percent of them went out on disability. Lest you think this figure has something to do with the very real dangers of firefighting, the figure for fire chiefs is even higher. Since World War II, every single fire chief has retired on disability, proving. I guess, the perils of desk work.

You could point out that the system is a fraud and you could point out that it takes money from programs that could use it, and you could say, as you always can say, that the taxpayer is being ripped off. All of that is true. The fact of the matter is that there are bills working through Congress to reform the system.

But that is really not the point. The point, instead, is that for the moment the abuse continues and for the moment no one is saying anything. From the mayor you hear nothing. Something called the Police and Firemen's Retirement Relief Board meets behind closed doors, answers questions from no one about anything, and makes a decision it does not even announce. Someone either gets disability or doesn't get disability, and no one has to account to anyone for what happens, and no one says a word about how all the fire chiefs in this city have to limp off their jobs.

Anyway, you could forgive someone if he thought this whole thing smacked of the buddy system and you could forgive someone for saying that a city with a system like this has no right to say anything to welfare cheats. You could forgive someone for saying that it reminds him of the old situation in the insurance industry where fraud became so entrenched people thought they had it coming. But what you cannot forgive is the attitude of city officials who condone or tolerate a situation that so obviously stinks, who say nothing in the face of such abuses.

They are the ones with the real disability.