Restaurateur 4th to Testify He Saw Barry Use Cocaine : Trial: Witness acknowledges that he had pleaded guilty to conspiracy to possess drugs and was testifying as part of a plea agreement.

An Iranian-born restaurateur testified Monday that Mayor Marion Barry repeatedly used cocaine over a period of years, starting in 1985 on the night that his Georgetown restaurant opened.

The businessman, Hassan Mohammadi, was the fourth witness to say that he saw Barry use cocaine. He said that he furnished the drug to the mayor, in powdered form, on about 30 occasions.

Rolling a dollar bill into the shape of a straw, Mohammadi showed jurors in federal court how he said Barry would sniff lines of cocaine while blocking off one nostril with his left forefinger.

“He bent over the coke and he snorted,” the witness said, as Barry’s drug-use and perjury trial entered its fifth week.

Barry, sitting at the defense table, grinned at jurors and spectators in the crowded courtroom during Mohammadi’s demonstration with the dollar bill.

Barry smiled again when Mohammadi testified that after using cocaine with another man in a private room above his restaurant, Barry had given a 10-minute speech to diners attending the grand opening of the restaurant, Pardi’s. “Everybody had a good time,” the owner told the jury.

Under questioning by prosecutor Richard W. Roberts, Mohammadi acknowledged that in May he pleaded guilty to conspiracy to possess drugs and was testifying as part of his plea agreement.

“Who was it you conspired with to possess cocaine?” Roberts asked.

“Mr. Mayor,” the witness replied. He said that based upon his cooperation, the government has agreed to recommend leniency at the time of his sentencing later this year.

According to Mohammadi, another Iranian-born businessman, Samad Arshadi, provided the cocaine for Barry to use on at least two occasions in Mohammadi’s restaurant and home. Arshadi, a former nightclub owner, will testify later for the prosecution.

Mohammadi testified that he and Barry both used cocaine several times on a trip to the Bahamas in November, 1987, shortly after he had delivered a small amount of the drug to the mayor in his City Hall office. He said that in February, 1989, he lied to District of Columbia police investigators by telling them that he had no history of drug involvement with the mayor.

Among the 14 charges on which Barry is being tried are three counts of perjury alleging that the mayor lied to grand jurors in denying under oath that he ever had used drugs with another former associate, Charles Lewis. Lewis testified earlier in the trial that he used cocaine with Barry and that both men had discussed how they could cover it up.

Earlier Monday, a small-time drug dealer testified that federal investigators apparently have lacked interest in any of her customers except Barry. Lydia Pearson, a prosecution witness, gave this assessment under cross-examination by Barry’s defense lawyer, R. Kenneth Mundy.

“Did the FBI or the prosecutors ever ask about any other customers besides Mr. Barry?” Mundy wanted to know.

“No, they did not,” Pearson replied.

The question seemed aimed at bolstering a defense contention that Barry has been singled out for prosecution by a largely white governmental power structure.