The executive branch of the federal government is packed with overseers, all charged with keeping their fellow public servants honest.

Cabinet departments and regulatory agencies, for example, have ombudsmen galore. The General Accounting Office, an arm of Congress, conducts investigations around the clock. And if things appear really fishy, Congress can conjure up an "independent prosecutor" to strut before grand juries, subpoena documents and make life unpleasant for any official within reach.Amidst all this ferreting and sniffing, however, Congress remains happily untroubled by the same treatment it dishes out to others. No ombudsmen, no investigatory agencies, no counsels peeking under the rugs of Congress itself.

In the latest case in point, the Heritage Foundation, a Washington think tank, has just uncovered yet another example of congressional arrogance and double standards.

A few years ago, Congress passed legislation requiring all government offices, including its own, to enact a written policy designed to stop employee drug abuse. The bill was the usual empty posturing - another instance of congressmen wanting to appear to be doing something while not really doing anything. But the agencies complied, though some of the policies are being challenged in court.

The Heritage Foundation decided to check how Congress itself was fulfilling this solemn self-mandate. The answer: not terribly well.

Of 100 Senate offices, only 48 have an office drug policy. The record on the other side of the Capitol building is even worse. Of the 435 House offices, only 97 have formulated such policies.

This doesn't mean, of course, that Capitol Hill is overrun with drug addicts or even that congressmen aren't serious about drug abuse. But it does signify, once again, that congressmen consider themselves above the law, even when they pass it themselves.