He is inmate No. 151492, perhaps the most infamous prisoner at the Allegheny County Jail.

Richard A. Poplawski, the accused killer of three Pittsburgh police officers, has a window, a cot, a latrine and the clothes on his back.

Other than that, his 8-foot by 10-foot cell is bare, and he's on his own.

Mr. Poplawski, 22, is being kept in administrative custody -- effectively solitary confinement -- for 23 hours a day. His one free hour is used for indoor recreation. He showers by himself and takes his meals alone.

Mr. Poplawski is not allowed contact with anyone from the outside world except for his lawyer. And jail officials have not granted him access to any reading material -- not even a Bible.

There are 25 other cells in his unit, and a guard sits in the middle of them all watching Mr. Poplawski through a window in each metal door -- just in case Mr. Poplawski tries to kill himself.

Warden Ramon Rustin said Mr. Poplawski is being kept out of the jail's general population until officials decide whether he is suicidal or stable.

Then there are the other reasons.

"We also need to be cautious about how the inmate population is going to treat him," Mr. Rustin said. "And then I'm a little concerned about my staff and their treatment of him.

"So far they've been extremely professional, and I would expect no less. But until I get a real good sense of how everybody's going to adapt to his stay here, I'd just like to keep him isolated for now."

Brian Ferguson, president of the Allegheny County Prison Employees Independent Union, said most guards are aware of Mr. Poplawski's presence and are being "professional and cautious."

Mr. Rustin said some inmates might view Mr. Poplawski as a hero for allegedly gunning down officers Paul J. Sciullo II, Stephen J. Mayhle and Eric G. Kelly on April 4 in Stanton Heights when they responded to a domestic disturbance call.

But not all of them.

"I've heard a lot of inmates have expressed condolences to law enforcement because they know police officers are suffering now," Mr. Rustin said.

The warden has had to grapple with his own issues over the incident. He is married to a Pittsburgh police officer -- Detective Jill Smallwood-Rustin.

"I understand how she feels, but both of us are professionals, so we've got to do our job," Mr. Rustin said.

"Part of my job is to make sure every inmate in here gets his day in court. That's pretty much it. We don't really talk a whole lot about it."