Five District of Columbia policemen who were fired by the police department as long as three years ago are being paid their full salaries, an average of about $20,000 a year, and are receiving regular pay increases while waiting for Mayor Marion S. Barry's office to review the charges that led to their firings.

In addition, another officer who waited two years for a decision from the mayor on his appeal received about $40,000 in salary and then quit the police force on Jan. 23 without having his case resolved.

The six policemen -- fired for offenses such as malingering, assaulting another police officer and carrying an unauthorized revolved while off duty -- have been paid a total of more than $121,000 while awaiting decisions on their appeals, sources have told The Washington Post.

"I know government money has been wasted," said Marlene Johnson, Barry's deputy legal counsel, who is assigned to review the cases and make recommendations to the mayor. "It's a horrible story, but I'm doing the best I can to give the police officers a fair shake and also to help the city government do better."

Johnson said she has delayed making recommendations to the mayor for several reasons. She said she has been plagued by staff shortages, incomplete case files on the officers and her own ignorance of police personnel procedures.

"When I came on [two years ago], the staff that I knew about discipline in the police department could fit on the head of a pin," she said. "I had to learn fast."

But a major factor in the delay, she conceded, has been her inability to accept the way the D.C. police trial board handles its disciplinary problems.

The police trial board -- the disciplinary arm of the police force -- recommended that the six be fired, and Police Chief Burtell M. Jefferson and former police chief Maurice J. Cullinane approved the firings following police department investigations and hearings on the charges against the officers. Johnson said she feels the trial board process is cumbersome and inconsistent.

In reviewing the board's recommendations in 26 cases, Johnson said she found that some officers were penalized more severely than others for the same offenses. She said some of the cases never should have gone to the trial board. There is no standard policy for determining penalties for an offense, a guideline she said she feels is critically needed.

However, of the 15 recommended firings she has reviewed so far, Johnson said she agrees with the trial board in all but one case. She said she is sending her recommendations on these cases to Barry and also will ask the mayor to modify a few of the fines set by the trial board.

Johnson said she soon will submit recommendations to Barry suggesting that various changes be made in the way that police trial board operates.

"The police trial board can't become a kangaroo court," she said. "In a way, I would rather be slow and try to be fair than be quick and [unjust]" to the officers, she said.

Sgt. Arnold Wiley, acting chief of the police department's employe relations office, said that in addition to reviewing the cases of the six fired officers, Johnson also is reviewing the cases of another 21 officers who were suspended without pay as long as three years ago.Wiley said their violations were so serious that they immediately were removed from police payrolls and duties while being investigated. Wiley said the six officers receiving pay are charged with less serious offenses, and therefore are allowed to collect paychecks until their cases are decided.

"If we could find a way to get rid of them we would. The fact that it takes the mayor three to four years to adjudicate the case doesn't bother them," Wiley said of the employes being paid while not working. d

Under District law, a police officer fired by the police department can appeal the decision to the mayor within five days. The mayor then must review the case and decide whether to reject, modify or uphold the department's recommendation. There is not time limit in which a decision must be made. Former mayor Walter E. Washington also took two to three years to review the cases.

The five fired officers who still are being paid are:

Jimmie Hill Jr., a seven-year veteran fired in December 1977 for malingering and lying in regard to outside employment. At the time, Hill was paid $14,035 and now gets $21,100.

Thomas R. Baker, a three-year veteran fired in February 1978 for breaking into another police officer's home and assaulting her after finding her with another man. His salary has gone from $17,561 to $18,485.

James H. Franklin, fired last April after eight years on the force, was charged with malingering. Franklin then was paid $20,045 and now receives $21,100.

Paul Wiles, a five-year veteran fired last June, was found guilty of carrying an unauthorized revolver off duty and several alcohol-related offenses, including drunken driving in Virginia. He was paid $16,725 at that time and now receives $17,605.

Joseph Bucior Jr., an 11-year veteran, was fired last August for failing to live within the required 25 miles of the Capitol and failing to report his correct home address and telephone number to his commanding officer within 24 hours. He was paid $20,875 at that time and now gets $21,919.

Information was not available on Bobby R. Barba, the officer who resigned last month after being fired in November 1978. Barba was being paid $21,000 annually at the time he resigned.