Fairfax County officials say they soon will ask the Virginia courts to referee one of the most complex property disputes in county history: who should get thousands of dollars in stolen jewelry and art objects confiscated from the home of convicted thief Bernard C. Welch Jr. There are more than 500 claims.

The burglary victims, as well as the federal government and the state of Virginia, have claimed the 1,200 to 1,400 items that remain in the custody of Fairfax police, according to Assistant County Attorney Robert M. Ross. The trouble is, Ross said, that many robbery victims are claiming the same items.

"Usually you have three or four people at most making claims over contested property," said Ross. "But not political subdivisions, Uncle Sam and hundreds of private citizens . . . . I don't know of any precedent for this."

It has taken Fairfax officials more than two years to sort through the more than $4 million worth of loot police seized at Welch's Great Falls home after his arrest in December 1980 for the murder of Washington cardiologist Michael Halberstam.

The largest chunk of the contraband was identified and claimed by burglary victims during public showings of the jewels, furs, figurines and silverware shortly after it was discovered in Welch's basement.

That still left about $1 million worth of jewelry and other precious items in a Fairfax police warehouse. Some of the more indistinguishable Welch items, including melted lumps of gold and nondescript jewelry went unclaimed and were seized by federal marshals and sold at auction last month to benefit a Washington lawyer who had won a damage judgment in federal court against Welch for burglarizing his home.

But what Fairfax officials call their biggest headache persists: the items that have been claimed by more than one person.

There are the three persons fighting over the three-quarters-inch silver bangle, and the two persons vying for the Gorham silver teaspoon and the four who want the gold ring, and so on.

Not all of the remaining Welch items are being fought over. Police have refused to release some items because burglary victims could not provide proof of ownership, said Stephen D. Danzig, the police officer originally in charge of the case.

"Most of the stuff we have left are not the most unique items you could describe," said Ross. "There isn't anything on this list that isn't worth something," he said, adding that many of the remaining items have more of a sentimental value to their owners.

Ross said he has received an average of 10 to 12 calls a week for the last year from some of the many Washington area homeowners that police said were victims of Welch's many burglaries. "Virtually all of them have been cooperative and very understanding," he said.

Even though Fairfax has no legal claim to the remaining Welch property, Ross said county officials decided to take the case to the Fairfax Circuit Court on behalf of the robbery victims. "The alternative was to have each of the individuals sue Fairfax County," said Ross.

Three county employes have spent weeks indexing and cross-checking the stolen items and the claimants on computer printouts, officials said. Ross said he plans to submit computer printouts as part of the lawsuit over the ownership. The county also will ask the courts to take custody of the valuables, which police have stored in Fairfax City.

The county's filing, expected in two to three weeks, will set off another chain of problems for officials. The sheriff's department and other area law agencies will be charged with delivering court papers to the more than 500 claimants, said Ross.

A judge, or a court-appointed officer, probably will be faced with setting up individual hearings on each piece of property. If insurance companies have paid claims for some of the stolen property, they may seek to intervene in the case, Ross said. Or the federal goverment, which has filed tax liens against Welch's home for unpaid taxes, could seek to have the entire matter handled by the federal courts, he said. Virginia has similar claims against Welch for unpaid state taxes.

"We don't know what will happen," said Ross. "We're dealing in uncharted territory . . . . We're just trying to put together something that will work."