A Pennsylvania state judge ruled late yesterday after a two-hour hearing that 55 D.C. inmates bused Friday to a private prison northeast of Pittsburgh may stay through the weekend but must leave the facility by 1 p.m. Tuesday.

The decision by Commonwealth Judge David W. Craig of Pittsburgh to allow the inmates to remain temporarily at the 268 Center in Cowansville, Pa., appeared to give the District a two-day reprieve in a two-week-long scramble to keep the inmate population at the D.C. Jail below the court-ordered ceiling of 1,694.

A jail official said last night that the inmate count was "right on the borderline, right at the cap," and other officials said that there was "absolutely no space at Lorton," the District's prison in southern Fairfax County. Sources said the D.C. Jail count last night was between 1,685 and 1,690.

"We are disappointed they are being allowed to remain there over the weekend and would hope that the District of Columbia would move more quickly to move them out of there as soon as possible, even before the 1 o'clock deadline on Tuesday," said David Runkel, a spokesman for Pennsylvania Gov. Richard Thornburgh, who had sought the order blocking the prison from admitting the inmates.

Craig, who ruled Friday that the inmates could not enter the 268 Center and then said the prisoners could stay overnight before beginning their eight-hour trip back to the District, said his latest decision was prompted primarily by the District's "utter lack of communications" with Pennsylvania authorities.

"The District had not conferred in advance with Pennsylvania law enforcement agencies or the Pennsylvania Department of Corrections as professional colleagues," Craig said after yesterday's hearing.

"The utter lack of communication and organization at the governmental level is at its root a real and present danger," he said.

Corrections Director James Palmer refused to comment about the situation last night.

Alvin Bronstein of the American Civil Liberties Union's National Prison Project said that for District officials "to have gone through that exercise without checking with state officials of Pennsylvania has got to be the height of stupidity and illustrates the chaos and their lack of thought."

Craig said he set the Tuesday deadline to allow the District enough time to provide for transportation and other facilities to receive the 55 inmates, all of whom have been convicted of misdemeanors, or less serious crimes.

In addition, Craig said, "the testimony and evidence indicates that this facility 268 Center was more of the nature of a halfway house than the nature of a minimum-security facility."

The District contracted with the private facility, about 50 miles northeast of Pittsburgh, after it became clear the city would be unable to open an emergency inmate facility near Capitol Hill.

On Friday, a D.C. Superior Court judge blocked the opening of the emergency facility in the old 9th Police Precinct station at 525 Ninth St. NE until at least Friday, primarily because of concerns about the safety of inmates in the event of a fire. The building has only an interior wooden stairway.

The crisis over the jail's inmate population began in August when U.S. District Judge William B. Bryant imposed the cap, but the situation was immediately eased when the federal government agreed to take all newly sentenced D.C. prisoners until the city could begin work on a new permanent prison inside the city limits.

The federal government ended that agreement in January, saying that the city had not progressed on a new jail. At that time, the jail was about 150 inmates under the population ceiling and most of institutions at Lorton had space for additional prisoners.

But in the past two months, despite emergency measures such as the early release last weekend of 67 persons about to be paroled, the city has run out of space to house prisoners, and almost daily for the past two weeks it has been in danger of violating the court order.

The federal government has said it will not consider resuming its agreement to take prisoners until the city has opened temporary shelter and decided on a site for a new permanent prison.

Congress has appropriated $30 million for a new prison, but Mayor Marion Barry, who insists that the new facility be built on federal land, has turned down three sites suggested by the Justice Department. Last week Barry sent his own list of sites to the federal government.

They are a 21-acre tract at the foot of the Frederick Douglass Memorial Bridge in Southwest, a 10-acre site along New York Avenue NE near the Washington Times building and 15-acre tract that wraps around the historic old brick kilns near the National Arboretum.

Yesterday morning, more than 100 demonstrators, many singing, carrying signs and chanting slogans, gathered at the foot of the Douglass Bridge to protest that area's inclusion among Barry's sites.

After listening to speakers that included City Council member Wilhelmina Rolark (D-Ward 8), the protesters formed a caravan of about 50 vehicles and drove from the site to Barry's home on Suitland Avenue SE, where they held a 10-minute, peaceful demonstration outside his house.

Some officials have indicated that because a portion of the tract is part of the old Naval Air Station adjacent to Bolling Air Force Base, it is not part of a city ward. However, Rolark maintains that the entire tract is part of Ward 8, in which Barry previously has promised he will not build a prison.

The controversy over the role of the private 268 Center represents what has become a nationwide debate over the participation of private enterprise in the criminal justice system that is faced with growing inmate populations and court-ordered population ceilings at many state prisons.

Because the issue of private prisons is such a new one, most states, including Pennsylvania, do not have laws regulating them.

"We do take a position opposed to private prison facilities," said Steven Ney, chief counsel for the American Civil Liberties Union's National Prison Project. "There is a serious constitutional problem with turning over the disciplinary functions of the government to the private sector and turning over decisions affecting inmate length of stay and parole status to a private agency."

"The Pennsylvania Department of Corrections cannot even inspect that place 268 Center without the permission of the owners," said Pennsylvania state Rep. David R. Wright, cosponsor of pending state legislation that puts a one-year moratorium on private prisons until regulations for them are passed.

Kenneth R. Tack Jr., vice president of 268 Center Inc., said in a recent interview that the facility opened in September after 25 months of planning and the $750,000 renovation of two large buildings.

The minimum-security facility, conceived at a time when Pittsburgh was under a court-ordered population ceiling at its jail, was designed to house its overflow prisoners and those from other county prisons. Before this weekend, it had held not more than 15, mostly for drunk-driving convictions. The facility closed temporarily in January because it was losing about $5,000 a month.

In an interview Friday, a spokesman for 268 Center said the prison was back in operation and the staff had been recalled.