The difficulty the Internal Revenue Service seems to have in policing itself deserves vigorous correction.

A year-long congressional probe of alleged misconduct by senior officials in the agency suggests the IRS may yet turn out to be another scandal-ridden federal agency.The House Government Operations subcommittee on consumer affairs has been investigating eight cases involving alleged misconduct up to the level of deputy assistant commissioner.

The IRS has had scandals in the past. Two years ago, 88 IRS employees were convicted of crimes that including embezzlement, selling narcotics and accepting bribes. In one scandal alone, more than $1 million in bribes were paid to IRS employees.

But three things set these scandals apart: evidence that they involve high-level officials, the failure of the agency's sizeable policing agency to resolve the problems, and the apparent punishing of employees who report the misconduct.

The latter problem is particularly disturbing. The subcommittee has investigated several cases where IRS employees who called attention to misconduct - as the law requires them to do - were subsequently demoted or fired.

Ideally, all government agencies should be above reproach. But it is particularly critical for the IRS - the agency that pursues criminal and unethical conduct more ruthlessly perhaps than any other - to adhere to the highest ethical standards itself.

Indications that IRS employees were punished for reporting misconduct is particularly disheartening. President George Bush wants to require such reporting from all federal employees as part of his ethics-in-government recommendations. But employees will be reluctant to adhere to such a requirement if they see such acts destroy the careers of other workers.