It was a campaign strategist's dream. Television crews clustered around the candidate, his chestnut hair rippling in the warm summer breeze. A few blocks away, the candidate's wife worked lunchtime crowds with baseball card-sized pictures of her handsome, grinning husband.

"I am here as duty requires me," said Virginia Republican gubernatorial candidate J. Marshall Coleman rather grandly as reporters and photographers surrounded him yesterday in front of the federal courthouse in Alexandria.

It was state Attorney General Coleman's day to lead the defense of Virginia's new drug paraphernalia law against a challenge by the Washington-based National Organization for the Reform of Marijuana Laws and a tobacco accessories trade association.

After nearly four hours of argument, District Judge Albert V. Bryan Jr. took under advisement whether to make permanent his earlier order blocking police in Alexandria, Fairfax and Prince William counties from implementing the drug law.

Meanwhile, Coleman's appearance coincidentally gave him valuable exposure on Washington television stations. It also happened to dovetail with a campaign stop last night at Wolf Trap Farm Park. Had Coleman interrupted his campaign to defend the commonwealth in court?

"I'm not going to touch that question," said a Coleman aide with a smile.

Lawyers for NORML and the trade group produced former Alexandria assistant prosecutor T. Rawles Jones and former U.S. attorney William Cummings to testify that the law governing paraphernalia sales is vague, overly broad and nearly impossibly for authorities to enforce.

"It would be extremely difficult for the average prosecutor to apply," Jones said.

Under Coleman's cross-examination, Cummings, who was testifying as an expert witness, conceded he had been personally involved in the handling if only two drug prosecutions.

Coleman countered with testimony by Arlington Commonwealth's Attorney Henry Hudson, who said he would have no difficulty advising police on provisions of the statute regarding a retailer's intent -- a key element of the law -- in selling bongs (a water pipe for smoking marijuana), roach clips, (devices for holding marijuana cigarettes) and other drug paraphernalia.

Cummings testified he believed "the average" law enforcement official would be mystified by the names of several drug implements specified in the measure.

"You mean a federal prosecutor wouldn't know what a bong was?" interrupted Bryan incredulously stirring laughter in the crowded courtroom.

Coleman -- who the aide said has made about 10 courtroom appearances as attorney general in his three years in office -- stumbled only once yesterday. As he launched into a line of questions about analogies between the drug law and certain obscenity statutes, Bryan cut him off abruptly.

"I don't want to open up that area," Bryan snapped. "The obscenity statute will have to stand on its own."

Similar drug paraphernalia laws are under court challenge in about 40 states, a law enforcement official said yesterday. Maryland's statute, based on a model drawn up by the Drug Enforcement Administration, was upheld by a federal court and is now before a federal appeals court in Richmond.

Attorneys for NORML and the tobacco accessories organization argued strenuously yesterday that the Virginia law violates the constitutional protection of free speech by encouraging police to seize NORML literature displayed in shops selling paraphernalia as evidence of a retailer's intent.

"This is pure speech directed solely at changing laws and educating the public," said lawyer John Zwerling. "We are not dealing here with how to make a bomb or how to smoke marijuana."

In his closing argument, Coleman disagreed, saying, "It's clear the act is directed at an evil the General Assembly has a right to do something about. . . . It (the law) passes constitutional muster."

Outside, with the cameras rolling once again, Coleman called the free speech issue "a red herring," adding, "The law is aimed at an industry that thrives on drug abuse." With that, the cameramen packed up and Coleman walked off down the street, surrounded by campaign aides.