Theodore R. Carr, one of three assistant chiefs of the D.C. police department, was appointed yesterday to be deputy chief in charge of personnel in the Prince George's department.

Carr, 48, will replace Lt. Col. Thomas Davis, the police department's highest ranking black, who was forced to resign in December because he told his subordinates to change the test scores of black applicants.

Carr, a 27-year police veteran who also is black, is retiring from the D.C. police department where he was in charge of administrative services -- including personnel -- since 1981. He begins his new job Monday.

Carr's responsibilities in Prince George's will include personnel, recruiting, training, internal affairs and race relations. He said yesterday that he knows he will be faced with some serious challenges, and added, "I hope my presence here will not represent just window dressing."

The new deputy chief comes to the department at a time when there is some tension between white and black officers. Blacks on the force have threatened to sue the department over what they say are discriminatory promotional practices and have been negotiating with the union on a settlement of that issue.

Except for Carr, there are no blacks on the Prince George's force who hold a rank above sergeant. The 900-member department has 176 black officers.

In addition, Carr's predecessor, Davis, was not particularly popular with whites or blacks because he was not a career police officer but a retired Air Force officer hired eight years ago to teach race relations at the police academy. In 1981, the County Council created an appointed deputy chief position specifically for Davis, whose mandate was to recruit more blacks and women. In recent months, however, training instructors, the Fraternal Order of Police and finally the chief, took exception to some of the methods Davis used to attain those goals.

Yesterday, County Executive Parris N. Glendening said Carr came highly recommended by both police executives and community leaders.

Police Chief Michael J. Flaherty said there were 105 applicants for the position. "Ted Carr quickly rose to the top from that group," Flaherty said. "He is tailored to the position he is filling."

However, rank and file officers in both the county and the District, expressed some reservations yesterday.

Tom Lennon, president of the county FOP said, "The people I talked to said he [Carr] was a capable guy, but a strict disciplinarian -- a hard liner."

Ronald Hampton, who heads a black police officers' organization in the District, concurred, adding that he did not believe that Carr has adequately addressed racial inequities in the department.

Reginald Riley, president of the Prince George's Black Police Officers Association, said yesterday that Flaherty ignored the organization's request to interview the finalists for the personnel job. Riley said he had heard from District officers that Carr is not aggressive and took no leadership role in the District. But Riley concluded, "We'll just have to wait and judge him on what he does."

Carr's new $48,000 salary will be supplemented by his District government pension, he said. The pension could add about $25,000 to his Prince George's salary, officials indicated.

Carr will be one of four deputy chiefs in the department, but is the only one serving at the pleasure of the chief.