Montgomery County Council members were so upset to hear that the police department had recruited just one black officer into its new training class that they called for a special hearing.

What they learned yesterday concerned them more: The lone black recruit changed his mind, opting instead to go to Prince George's County and become a firefighter.

"So as of today, there are no blacks?" council member Isiah Leggett asked Police Chief Donald E. Brooks.

"That's a severe blow," said council member Rose Crenca.

The new police officer class sworn in yesterday contains 37 white males, three white females, one American Indian male and two Asian males. There are no blacks and no Hispanics.

Brooks, along with the county personnel director, told a joint session of the council's personnel and government services committees that the low numbers of minority recruits is an "anamoly" for a department that has worked hard at affirmative action.

They pointed out that the overall composition of the department is 11.2 percent black, roughly the same percentage of blacks in Montgomery's population.

"It's important for this council to know we haven't been sitting on our hands, not putting forward any effort, because we have been," said Brooks, who has come under criticism for his handling of recruitment efforts. The Montgomery branch of the NAACP first raised the issue, alleging that Brooks had a dismal record.

Brooks came under further criticism when the official he selected to improve recruitment efforts resigned less than a week after his appointment because of revelations that he had been accused of sexual harassment in 1983 by two female officers.

Leggett, the only black member of the council, chaired yesterday's meeting, but he stressed that the session was not to point fingers.

The questioning became testy at times, however, with Brooks clearly defensive over suggestions that his department did not pay enough attention to minority recruitment.

"We have always been successful" in minority recruiting, Brooks said, but "this is the one time that that didn't happen . . . . I'm not going to criticize my people."

Council members suggested that the county hasn't kept pace with neighboring jurisdictions, and used the defection of Montgomery's black recruit to Prince George's as a prime example.

Leggett said county officials need to look at a variety of benefits to sweeten a recruitment package. Prince George's, for example, offers signing bonuses, use of a vehicle upon graduation and relocation expenses.

Brooks is to report back to the council with proposed improvements.