Alexandria Police Chief Charles T. Strobel was found not guilty yesterday of lying to a federal grand jury that spent more than a year investigating allegations of corruption in his police department.

"You can find justice in Alexandria," Strobel told reporters a few minutes after a U.S. District Court jury cleared him of six counts of perjury and six counts of obstruction of justice in a case that had renewed talk of scandal within Alexandria city government. Early last year a special state grand jury cleared the chief of separate allegations that he thwarted a drug investigation.

Strobel, 48, a career officer on the Alexandria force and its chief since 1977, showed no emotion yesterday afternoon as the jury read its verdict after eight hours of deliberation. His wife Paula cried softly in the gallery.

"I could not believe that after 28 1/2 years of law enforcement I would have found myself sitting at a defendant's table answering to a system I have so commendably served," said Strobel, who has been on leave with pay since his indictment in February. "Let's get back to business." He plans to return to work today.

"This case was a defense lawyer's dream: an innocent client and a bum rap," said attorney Plato Cacheris, who led Strobel's defense in the three-day trial in Alexandria. Strobel pleaded not guilty and Cacheris presented no evidence, arguing that the government's case was without merit.

One juror, who asked not to be identified by name, seemed to agree. "It wasn't all that clear why they had him there in the first place," the juror said.

U.S. District Judge Richard L. Williams called the case "a scarring situation for Alexandria" and told Strobel after the verdict: "I hope that all future and pending cases will be forgotten and you and other citizens of Alexandria go about more important endeavors."

Acting U.S. Attorney Justin Williams and the Justice Department's Public Integrity Section prosecutor Peter George, who directed the grand jury probe, declined to comment on the verdict.

The acquittal should end a long and divisive battle within the city over Strobel's management of the police department. That battle broke into the open in late 1984 after the Alexandria Port Packet published a story that said Strobel had halted an investigation into cocaine use and distribution at a city restaurant.

In February 1985 Charles E. Beatley, then mayor of the city, demanded that Strobel be placed on leave, setting off a furor that some said led to his defeat in the May elections. Several days later Strobel not only was cleared by the state grand jury but was praised for his administration of the city police force.

Almost a year later a federal grand jury issued a 67-page indictment charging that Strobel had "testified falsely and evasively" when questioned about his knowledge of allegations of sexual misconduct by three area policemen. The chief did not contend that he was unaware of the allegations, only that he didn't recall details of them when asked by the grand jury.

At the trial federal prosecutors presented four witnesses who testified they brought allegations of sexual misconduct by an Alexandria police officer and two Fairfax County vice officers to Strobel on at least three occasions during the 1970s. The four, all former or current Alexandria police officers, said Strobel either failed to act on the allegations or told them not to investigate them.

Under cross-examination, however, the witnesses said they could not recall details of the times they spoke with Strobel. One, former Alexandria police officer Louis Pugh, admitted he had given erroneous testimony to the grand jury in three instances.

Throughout his testimony before the grand jury, Strobel repeatedly said he could not recall the occasions on which he was brought the allegations or their specific contents. At other times he said he recalled the allegations in a general sense. He denied stopping any investigations into them.

While the federal investigation was under way, Strobel suffered two setbacks. City officials decided to split the city's consolidated public safety department, which he had headed, back into separate police and fire departments.

Last summer two police officers won $15,000 civil judgments against Strobel after a federal jury found he had violated their constitutional rights by punitively transferring them. That case is on appeal.

After he was cleared by the state jury, Strobel filed libel suits against the Port Packet, the Journal newspapers and an Alexandria attorney, Mary Craig, but he withdrew the suits after he was indicted by the federal grand jury. His lawyers then said they would refile the suits once he was acquitted.

"That's something we'll have to sit down and discuss," attorney Susan Cardenas said after the verdict.

"There'll be scars forever," said Lt. Arthur Bratcher, commander of the department's vice and narcotics section and a Strobel supporter. "I hope everybody is big enough and professional enough to forget it and move on."

A group of Alexandria officers who had raised some of the allegations against Strobel were not happy with the verdict. Officer Joseph Morrash, one of the two police officers who won the civil lawsuit against Strobel last summer, said, "It's a divided department, it always has been. Some people are overjoyed, others are furious."

Port Packet reporter Alicia Mundy, whose reports led to the special state grand jury, declined to comment.