Jurors in the trial of Garrett Eldred Wilson, who is to go on trial July 19 in the 1987 death of his infant son, will be able to ask questions of witnesses, a judge ruled yesterday, marking the first time the unusual practice will be employed in Montgomery County.

Montgomery County State's Attorney Douglas Gansler (D), who will try the case personally, proposed that the technique be allowed in the Wilson case. It will be Gansler's first trial as state's attorney.

The State of Arizona and several other jurisdictions in the country, including D.C. Superior Court, permit juror questioning.

Wilson is charged in the 1987 death of 7-month-old Garrett Michael Wilson. The elder Wilson also has been charged with murder in Prince George's County, where he is being held without bond, in the May 1981 death of his 2-month-old daughter, Brandi Jean Wilson.

Under Gansler's proposal, supported by Wilson's attorney, Barry Helfand, jurors will be allowed to write questions for each witness once the lawyers for both sides conclude their questioning. The questions will be reviewed by the judge, prosecutor and defense attorney and then read to the witnesses, if they are not objectionable on legal grounds.

"It's a way of involving jurors," Gansler said. "It's not a prosecution tool; it's a way of getting to the truth."

But Circuit Court Judge Ann S. Harrington was not so sure. "I can see it being very bad for everybody," Harrington said, envisioning massive delay as jurors pepper the witnesses with "hundreds of questions."

"I don't know whose idea this was," she said.

Gansler, who has tried cases in which juror questioning was allowed, said the approach does not add significantly to the length of trials.

Ultimately, Harrington decided to approve the attorneys' joint motion, with the proviso that Helfand is allowed to stop it.