The spectators in the crowded hearing room in Silver Spring leaned forward in their chairs yesterday and listened intently as Mike Epstein talked about his disability.

"Sometimes people don't understand me, because of a birth defect," said Epstein, 28, who may lose his Maryland driver's license despite having been found blameless in an automobile accident last April.

"My muscle coordination is pretty good . . . I don't take medicine except when I go to the dentist, or the doctor wants to be on the safe side" during an illness, he said.

The hearing, at the Maryland Motor Vehicle Administration, was believed to be one of the first in the nation involving mental retardation as a possible cause for suspension or revocation of a driver's license. Hearing officer John P. Wade took the case under advisement and is expected to issue a ruling within 20 working days.

After the accident April 5, in which a 15-year-old raced in front of Epstein's Plymouth Valiant and the youth was critically injured, the investigating police officer recommended that Epstein be reexamined on his ability to drive a car.

Epstein "appeared to be mildly mentally retarded," and had difficulty in understanding or relating to what had happened, Montgomery County police officer Joseph C. Niebauer wrote in his report.

Epstein appeared yesterday accompanied by two civil rights lawyers.

"I suggest the police officer was uncomfortable with the way Michael was speaking," attorney Victor M. Glasberg told Wade. "But that is no reason for taking action with regard to his license."

Wade, who said at first he was unable to understand Epstein's slow, labored speech, but later appeared to adjust to it, asked about Michael Epstein's IQ score.

"What is the point of questioning a man in public about his IQ?" demanded attorney Jason Amster. "He passed the driver's test, [and] they don't give an IQ test before they give you the driver's test, do they?" Amster asked.

Wade agreed, but said the IQ test, one of many tests used to determine intellectual potential, "may be relevant to his ability to function."

Epstein's mother, Esther, testified that her son had taken his last IQ test 19 years ago, when he was 9 years old. His score at the time ranged between 85 and 100, she said, which by today's standards would place someone in the category of "dull/normal." A score of 100 is considered "normal."

There is no minimum IQ requirement for obtaining a Maryland driver's license, according to Joseph L. Lupinek, director of the state transportation office's hearing section, who made a special trip from Baltimore yesterday to attend the hearing.

Epstein, a GS-3 employed by the U.S. Office of Education, told Wade he had never had an accident in the 2 1/2 years he has possessed a Maryland driver's license.

Depending on Wade's ruling, Epstein could lose his license, or be ordered to undergo further mental, physical, or driving tests. Epstein declined comment outside the hearing room "until the 20 days are over," he said.