Arlington County Commonwealth's attorney William S. Burroughs is trying to search the files of a criminal defense lawyer in hope of finding evidence aginst a client of the attorney.

The prosecutor sent a county police detective, Philip J. Nielson, into the office of lawyer Benjamin N.A. Kendrick yesterday with a search warrant to look for a pawn ticket for stereo equipment that was allegedly stolen and then pawned by a man Kendrick is representing on a grand larceny charge.

But Kendrick objected to the search, which had been approved by a county magistrate, and called Burroughs and other defense lawyers, according to Craig Sawyer, one of Kendrick's lawyers. Burroughs later in the day agreed to have a circuit court judge decide whether he had the right to search Kendrick's files for the pawn ticket.

"It is unique anywhere (to do this but we felt it was necessary," Burroughs explained. "All we're trying to do is obtain one piece of evidence which is in the hands of an attorney. We didn't want to force (Kendrick) into an obstruction of justice charge so we made arrangements to go to court" to test the validity of the search.

Sawyer and other defense lawyers said Burroughs action amounted to a challenge to the constitutional right to privacy and privileged attorney-client relationships.

"All criminal lawyers talk to clients all the time and if one lawyer's office can be (searched) by the government then nobody's safe," Sawyer said. "Most criminal defense lawyers feel that this (action) is frightening."

It could not be determined whether Kendrick has the pawn ticket. "I don't know and that's not the issue," said another of his attorneys, William Moffitt of Alexandria. "It's between Benny and his client. This challenge is one of the most serious things I've been involved in."

Sawyer said that Nielson demanded to search Kendrick's files for the pawn ticket and told Kendrick he would be arrested if he tried to prevent the search.

"Benny knew he was in big trouble," Sawyer said, "so he immediately got on the phone and started calling everyone he knew."

Late yesterday morning, as Kendrick's attorney friends gathered at the county courthouse, Arlington Circuit Court Judge Paul D. Brown said that he would decide the issue Monday morning.

However, after a meeting with three of Kendrick's attorneys yesterday afternoon, Burroughs said he would request a postponement of Monday's scheduled decision for several days "while we do some legal research."