A Northern Virginia man was sentenced yesterday to four years in prison for directing a group that sold advice on how to cheat the government on income taxes. Two others were sentenced to lesser terms.

"I reject the martyrdom presentation to the court as an excuse," Judge Albert V. Bryan Jr. told the defendants in U.S. District Court in Alexandria. "Dissatisfaction with the tax laws does not excuse the crimes."

Burton D. Linne of Arlington, described by federal prosecutors as the head of several tax protest groups, was convicted on 24 counts, including conspiracy to defraud the government, mail fraud and failing to file a 1984 income tax return despite a salary of $74,425. Linne maintains that the income tax is unconstitutional.

"My sin is that I became too effective in pestering," Linne said in court. He said if he was less vocal in his protests, the government wouldn't have investigated him.

Two of Linne's colleagues, Jack O. Slater of Annandale and John C. Imlay of Arlington, also were sentenced to prison. Slater received 18 months and Imlay was ordered to serve six months. Bryan said Slater's involvement was "not as egregious" as Linne's and that Imlay "was led and not a leader."

Slater and Imlay were each convicted on 20 counts of conspiracy to defraud, mail fraud and failing to file income tax returns.