A Massachusetts District Court judge ruled yesterday that state laws prohibiting the use of cocaine are unconstitutional.

Judge Elwood S. McKinney '38, who said last month he wanted to try cocaine in order to determine for himself whether the substance is harmful, said in a decision delivered yesterday that the drug is less harmful than cigarettes or alcohol.

McKinney dismissed charges of cocaine possession against Richard Miller, saying the case against Miller was "predicated upon a statutory scheme which violates defendant's rights to due process of law."

Attorneys involved in the case disagreed about the potential ramifications of McKinney's decision.

Martin G. Weinberg, Miller's defense attorney, said yesterday the decision set a precedent that will significantly affect prosecution of cases tried under Massachusetts's cocaine laws. He said McKinney's decision will make it difficult for police to arrest people for violations of the state cocaine statute.

Court officials said yesterday the decision does not set a precedent, and will have no effect on enforcement of the state's cocaine law, the Associated Press reported.

Under state law district courts--the lowest court level in the state judicial system--do not have the power to set precedents.

James P. Hayes, prosecuting attorney in the case, said yesterday that people who use cocaine will continue to face possible arrest.

A Precedent?

"This case has no precedent-setting effect," Hayes said.

Convictions for cocaine possession in Massachusetts carry a maximum sentence of one year in jail and a $1000 fine.

McKinney said in his decision that the state's present cocaine laws violate the Fifth and Fourteenth Amendments to the United States Constitution. Unless laws benefit the public interest, "legislation restricting individual freedom is a violation of due process of law," the decision stated.

The decision is "a very important and heroic first step toward eliminating victimless crimes," Alan M. Dershowitz, professor of Law, said yesterday. He added that he believes it is "terribly important" for "one judge to be willing to go out on a limb" for the cause of individual freedom.

McKinney attracted attention last month when he expressed an interest in sampling cocaine while holding a preliminary hearing in Miller's case. He finally abandoned the idea when publicity threatened to turn the trial into a "circuslike atmosphere," Weinberg said.

No Coke Sales

A Store 24 employee contacted yesterday said that even if the sale of cocaine were legalized, his store would probably not sell the drug because the "theft risk" would be too high.