Confirming what had been an open secret for several weeks, Prince George's County Executive Lawrence J. Hogan announced yesterday that John W. Rhoads will remain as police chief, the department will be reorganized, and blacks will be appointed to high level jobs.

Hogan said Monday that he had not yet made a decision on Rhoads' future. Yesterday, however, Hogan said he told the controversial chief the following day that he wanted him to remain.

At the same meeting, Hogan told Rhoads he had decided to hire a civilian public safety director to oversee the police and fire departments, the county detention center and the county's office of emergency preparedness.

Hogan said yesterday that former D.C. police chief Maurice J. Cullinane was "my first, second, third and fourth choice," for the public safety post, and added that Cullinane "wants it very much," but has yet to persuade his wife that he should return to work after retiring one year ago on a disability pension.

The reorganization that Hogan hopes will bring Cullinane to Prince George's will also, he said, move at least two blacks from outside the police force into new, high level department positions reporting directly to Rhoads. Currently, a sergeant is the highest ranking black on the police force -- which is 92.2 percent white.

"I want to send a message to the rank-and-file police, to the Fraternal Order of Police, and to the community that a new era is dawning for the police," Hogan said. "Latent or patent racism by the police will not be tolerated anymore, if it ever has been."

Hogan said his reorganization plans, which will have to be enacted through legislation in the County Council, will also mean promotions for some county police officers. He added that he expected several older, high level police officers to retire by July 1, thus creating openings.

Rhoads said he was pleased to stay on and said he supported Hogan's reorganization plans. "I've always been in favor of the public safety concept and my first choice for the job would be Cullinane."

Laney Hester, president of the county's Fraternal Order of Police, said that Hogan's announcements came as a surprise to him. "I really don't want to say too much until I've had a chance to talk to Mr. Hogan," Hester said yesterday.

Hester said he had thought Hogan would be unable to hire persons outside the police force in high level positions unless voters amended the county charter. "I know Winnie Kelly wanted to hire blacks up high but he couldn't because of the law," Hester said. "I'm not sure how Hogan will do it."

But Hogan said that the county attorney's office had been working on his proposed reorganization for several weeks, and "the present consensus is that we can do it with council legislation.