The District government has renegotiated its contract with city police officers and has agreed to give them a 20 to 22 percent pay raise over a three-year period beginning Dec. 1. The new agreement discards a controversial, two-tiered bonus and salary plan negotiated earlier this year, according to union officials.

Larry Simons, president of Local 442 of the International Brotherhood of Police Officers, said he signed the agreement Tuesday night along with Donald Weinberg, the city's chief labor negotiator. Flyers announcing the development were distributed by the union to the city's police officers.

The agreement calls for a 6 percent raise on Dec. 1, an additional 7 percent next October and from 7 to 9 percent in October 1983, depending on fluctuations in the cost of living.

A spokesman for Mayor Marion Barry said he "has not seen the agreement" and would not comment. Weinberg could not be reached for comment.

Officer Gary Hankins, a representative of the Fraternal Order of Police, which is involved in a bitter struggle to replace the IBPO as bargaining agent for city police officers, said the raises were "a last desperate act" by Barry and the union to mollify rank-and-file officers who criticized several provisions of the union's original contract when it was signed last summer.

That agreement provided for one-time-only bonus payments of about $1,000 in each of the first two years of the three-year agreement, and an increase in the third year based on the cost of living. The 6 percent increase provided in the new agreement will mean a raise of about $1,260 annually for an officer who earns $21,000 a year, the average salary in the department.

The percentage increase is seen by officers as preferable to a bonus system because raises resulting from it will become part of their base salaries, and will be a factor in computation of their pensions.

Simons acknowledged that the union decided to go for the percentage increases instead of the bonus plan because of vigorous opposition to the earlier contract. Several hundred IBPO members resigned from the union in protest of the initial contract, and joined the FOP. The IBPO has about 1,400 members, according to Simons, down from about 2,600 when the initial agreement was reached.

Simons rejected complaints from the FOP that the higher raises resulted from the mayor's attempt to preserve the IBPO as bargaining agent. The IBPO was one of the first unions to endorse Barry in his 1978 campaign for mayor.

At stake is the right to collect about $440,000 a year and represent the department's 3,300 rank-and-file officers who contribute by payroll deduction either $5.50 every two weeks in union dues or $5.19 in "service fees" if they are not union members.

The IBPO won the service fees as part of the initial contract this year. The FOP has charged that the fees were a "windfall" for the union, and were designed by the city as a lever to persuade the IBPO to agree to the bonus payments instead of salary increases, thus saving the city thousands of dollars.

The IBPO is under orders from the city's Public Employees Relations Board to negotiate a date for a representational election with the FOP.

The agreement with the police union is the first reached by the city with any union involving salary scales. The District is involved in several first-time negotiations with other city workers over pay provisions.