AFTER MONTHS OF searching and countless unhelpful hints and barbs from the police union president, Prince George's County is getting a new police chief. County Executive Lawrence J. Hogan has offered the job to James R. Taylor, chief of the Petersburg, Va., department. If approved by the council, Mr. Taylor will assume command of a force that has had some fairly stormy relations with the community it serves. And judging from the way certain county council members are behaving, the next police chief will not have the flexibility needed to do the best job with the force. They have been blocking Mr. Hogan's efforts to open the top ranks of the force to minorities or other top law-enforcement talent from outside the force.

To his credit, Mr. Hogan hasn't stopped trying. First, he said he wanted to fill a vacant lieutenant colonel's job with a black officer from another law enforcement agency. But in May, council members, abetted by the police union, found a cunning way to keep the top ranks closed: they voted to cut out money for the job. Some did offer a flimsy explanation to the effect that if Mr. Hogan wanted a high-ranking black officer, he could fill the vacancy with one of the 55 blacks then serving on a force of nearly 840 officers. But when the highest-ranking black is a sergeant and there's one black-sergeant on the force, the options are not what you would call great.

Council members had another suggestion: why didn't Mr. Hogan create a new position that would be exempt from regular hiring and promotion requirements? The catch here was that this would require voter passage of an amendment to the county charter. If that's what it takes, all right, said Mr. Hogan -- who then asked the council for approval of a referendum on whether to let the police chief search beyond the force for lieutenant colonels.

So what did the council do next? Last week, by a tie vote, members defeated the referendum proposal. As Mr. Hogan noted, if he were a black officer, he would be upset, and "if I were a member of the black community, I would be very upset. If I were the new police chief, I would be very upset." For that matter, he concluded, any voter in the county should be upset. Residents throughout the county should welcome the continued transformation of their police force into a more responsible and representative corps. And members of the county council should reflect this concern by rejecting any more partisan or union attempts to block a most constructive change.