An Alexandria police lieutenant violated department rules when he failed to report for about two months an allegation of misconduct against a narcotics officer he commanded, said the deputy police chief.

Lt. Arthur L. Bratcher, who heads the Alexandria Police Department's vice and narcotics unit, should have reported immediately an allegation that one of his officers had tipped off the targets of a drug probe, Deputy Chief John Streeter said.

Bratcher was told in April that David B. Goldberg, a narcotics officer who resigned Aug. 7 after being asked to take a polygraph test, might have compromised an ongoing probe, Streeter said. But the police department's internal affairs unit did not learn of the allegation against Goldberg until late June or early July, he added.

Streeter heads an internal investigation trying to determine what prompted Bratcher's failure to report the allegation and whether the drug probe, which is still under way, was jeopardized. He is to report to City Manager Vola Lawson by Tuesday.

Streeter said that so far there have been no allegations that Bratcher, a 33-year veteran of the Alexandria Police Department, leaked information or attempted to tamper with the probe.

Bratcher "may have had a reason for the method in which he handled this," Streeter said in an interview with The Washington Post. "He may have felt that if the officer had tipped someone off and he was hauled in for questioning, the officer then would have no incentive not to blow every case he knew about."

But Streeter said that Bratcher's action clearly violated department rules, which require that Police Chief Charles T. Strobel be notified immediately when an officer is accused of wrongdoing. The allegation against Goldberg "was contained within the vice and narcotics division" for about two months after it was made, Streeter said. "It did not go forward at that time."

Bratcher could not be reached yesterday and previously has declined to comment on his handling of the allegation. But in a memorandum he circulated to vice and narcotics officers Friday, he said that allegations of wrongdoing on his part are "the work of a vindictive, devious, sick and warped personality."

"If I am personally, or my position, is the target of these false allegations, innuendos and inferences, I welcome the challenge," he wrote.

According to Streeter, the drug probe that was allegedly jeopardized by leaks is being conducted by a task force of officers from several Northern Virginia localities, the Virginia State Police and the Drug Enforcement Administration. None of the targets of the probe has been charged with any crimes.

Streeter said that in late April, an informant told Alexandria police officers that one of the primary targets of the probe had learned he was under investigation. The informant said the target had been tipped off by Goldberg, who knew the person and participated in sports activities with him, according to Streeter.

The officers immediately told Bratcher of the allegation, but the department's internal affairs investigators did not learn of it until late June or early July, Streeter said.

Goldberg's lawyer, James C. Clark, said yesterday that Goldberg had never been confronted with the informant's allegation by police officials and that Goldberg had done nothing wrong.

"Dave decided to change jobs, and it was a personal decision," Clark said. "I wouldn't place too great a connection between his decision to resign and a polygraph test. People change jobs for a lot of reasons. There's nothing for the police department to investigate."