Robert L. Williams, the man accused of killing seven people when his car plowed into a Southeast Washington bus stop last Aug. 25, told one emergency room doctor that he had drunk "some champagne, some beer and some Hennessy" at a wedding that day and told another he had used cocaine and heroin, two doctors testified at a D.C. Superior Court hearing yesterday.

Williams, 42, whose criminal trial is set to begin this week, is charged with seven counts of second-degree murder while armed in what authorities have described as the worst traffic accident in D.C. history. He has pleaded not guilty to the charges.

Seven persons, including two baby girls, were killed when, according to police, Williams drove at a high speed in the wrong direction on M Street SE, ran over the median and veered across M Street, then plowed into the crowd at the bus stop in the 200 block. At the time, Williams was on parole from prison in Virginia, where he had served part of a 20-year sentence for bank robbery.

Yesterday, the first details of how the accident allegedly occurred were made public in a suppression hearing before Judge Eugene N. Hamilton, who will preside at the trial.

Defense attorneys are asking the judge to "suppress" or block the use of the doctors' statements and statements Williams allegedly made to police, asserting that they were made in violation of Williams' constitutional rights against self-incrimination. Assistant U.S. Attorney Charles B. Hall, however, has argued that Williams was properly advised of his rights.

Yesterday, Dr. Donald C. Thomas III, who was director of emergency care at D.C. General last August, testified that Williams, whom he saw when he was brought into emergency, "admitted to me he shot up some heroin and cocaine earlier that day, and had a couple of a drinks at the wedding he'd been at."

Dr. Clarence Warner Jr., an intern at that time, testified that Williams told him in the emergency room that he was "coming from a wedding reception," and had drunk "some Hennessy," "three beers" and "two glasses of champagne." Warner also testified that Williams did not mention taking any drugs.

Attorneys Mark Carlin and David DeBruin, of the Public Defenders Service, have argued in court papers that these statements are "confidential" and that Williams had the "right to cooperate fully with his treating physicians" without fear that his statements later might "be introduced against him in a criminal trial."

They also argued that Williams, who was hospitalized after the accident, was not referred to the court system for appointment of a lawyer until Aug. 27 -- about 45 hours after the accident and also after he was interviewed by police.

However, D.C. police Officer John D. Killian, who interviewed Williams at the hospital that day, testified that he read Williams his rights and that he said he was willing to "answer some questions" without an attorney present.

In the statement, introduced in court yesterday, that Killian testified he took from Williams that day, Williams said he had "a couple of beers and two small glasses of champagne" at the wedding reception Aug. 25, "quite some time" before the accident.

According to the statement, Williams described the accident this way: "I was driving up M Street, and I remember something hitting my windshield. I assume that I lost control of the car and that's all I remember. Next thing I know someone was pulling me out of the car."