Former Alexandria prosecutor William L. Cowhig has returned to Virginia to face allegations of professional misconduct to be heard today in Richmond before a Virginia State Bar Association panel.

Cowhig, who could not be reached yesterday for comment, was acquitted in two highly publicized trials of charges related to the operation of bingo games in Alexandria. He resigned his post in February 1979 shortly after the wife of a drug defendant accused the former prosecutor of soliciting and receiving sexual favors from her in exchange for leniency for her husband. Cowhig has consistently denied the allegations, and his attorney, James Lowe, has denounced the trial as "clearly political." a

Lowe said Cowhig, now a baker in Florida, did not have to return for the closed hearing today, but apparently was coming for "personal" reasons to clear his name and retain his license to practice law. Cowhig has "no intention at this time" to practice law again, Lowe said.

A special prosecutor, appointed in 1979 to investigate the allegations, found no cause for criminal prosecution but referred the case to the state bar association. A local bar panel first heard the charges last March. Under the bar association's rules, that panel could have dismissed the charges, issued a private reprimand or referred the matter to the state disciplinary panel in Richmond if it felt the allegations were serious enough to warrant possible disbarment or suspension.