The greatest obstacle that Pittsburgh police officers faced when responding to Ka'Sandra Wade's house after she called 911 on New Year's Eve was a closed front door.
When the officers came to Ms. Wade's Larimer home late Dec. 31, Anthony L. Brown refused to let them into the house and instead spoke to them through a window.
Had he opened the door, a nationally recognized police policy expert said, Zone 5 Officers Louis Schweitzer and Lance Hoyson might have been able to spot any telltale signs of trouble: if Mr. Brown's clothes were torn, for instance, if there was blood, or if Ms. Wade could be seen.
Any one of those signs of distress would have given the officers a reason to investigate further, even though they did not have a warrant.
"I know a lot of officers ... would just gently push their way through the door and say, 'Sir, we've just got to see for ourselves if this woman is OK,' " said Thomas Aveni, executive director of the Police Policy Studies Council, a police think tank in New Hampshire.
"Once you've been locked out of a home, kicking a door is very different. This guy circumvented all of that by talking to them through a window," Mr. Aveni said Thursday. "This was probably the smartest thing he could have done, and from the officers' point of view, it was probably the most problematic."
The U.S. Supreme Court has upheld warrantless searches in certain circumstances. Pittsburgh police policy allows officers to enter a home without a warrant when "exigent circumstances" give them probable cause.
Elsewhere in the policy, the department says, "Exigent circumstances may ... exist where there is a continuing danger, or where officers have a reasonable belief that people are in need of assistance."
Officers left 528 Lowell St. without speaking to Ms. Wade following her disconnected call to 911.
Nearly 24 hours later, police returned to Lowell Street after worried relatives of Ms. Wade's asked them to check on her. Police found Ms. Wade, 33, had been shot to death inside her house.
Later that night when police went to speak with Mr. Brown, he refused to let them into his North Point Breeze apartment and a standoff ensued during which he killed himself. During the standoff, Mr. Brown, 51, admitted to shooting Ms. Wade and suggested in a note that police could have saved her.
It is not known exactly when Ms. Wade died or whether she was still alive when the officers arrived. But what is certain is that a variety of factors came together on New Year's Eve that might have complicated the response to her 911 call.
Ms. Wade's call around 10:38 p.m. came from a cell phone, making it difficult to confirm that she was indeed calling from her home. She was reportedly calm when requesting police, according to 911 records.
Around the time of the call, there would have been a shift change of supervisors at Zone 5. The incoming supervisor would have been preparing for an 11 p.m. roll call, checking the shift's manpower and attending to other tasks.
Additionally, a disconnected 911 call from a calm woman might not have sounded alarming to a police supervisor -- or even an officer -- who hears such calls regularly, according to one Pittsburgh police veteran, who was not authorized to discuss the matter and asked for anonymity.
"That's probably the worst time to hear a call, is 15 minutes prior to the roll call," said the officer, a supervisor with more than 10 years of experience who was not directly involved with the situation.
"With that time of day and that kind of call, it's conceivable the supervisor didn't even hear it," the supervisor said. "It's almost like a burglar alarm in my mind. Any given day, there are three to four hang-up calls that come in."
Typically, there could be multiple supervisors on a shift in a police precinct -- a lieutenant and up to several sergeants. Police have refused to identify the supervisors on duty during Ms. Wade's call.
It is not clear what role or responsibility the supervisor should have had in directing the officers' actions after Mr. Brown told them everything was fine and refused to grant them entry or answer other questions.
The Pittsburgh police policy governing radio communications, a copy of which was obtained by the Pittsburgh Post-Gazette, says "It shall be the responsibility of the shift supervisor to monitor all radio transmissions ..."
The policy also states: "The shift supervisor shall readily be available to provide assistance to units in the field who are handling calls for service ... When an officer needs assistance in handling a call, it shall be sought from the shift supervisor."
Records provided by Allegheny County from the 911 center do not indicate that any police supervisor was involved in the incident.
The veteran supervisor said there must be a balance between micromanaging officers and letting officers make their own decisions.
"I have to put my faith in the guys out there who handle it. Should I have heard [the call]? Yeah," the supervisor said rhetorically. "But I've got a lot of things going on, and I'm probably the only one working New Year's Eve ... If every call these guys go to I have to be asked what to do, then I should go answer the calls myself. There has to be a balance."
Ultimately, the most critical point in how the 911 call was handled might come down to the conversation Mr. Brown had with the officers. What was his demeanor? What did he say? Was he calm, convincing and credible? At one time, three people knew. But now one of them is dead, leaving only Officers Hoyson and Schweitzer with that firsthand knowledge.
Homicide detectives questioned the officers Jan. 3 as part of their investigation into the deaths of Ms. Wade and Mr. Brown. The matter is also under internal investigation, and the district attorney's office is reviewing the situation.
The local branch of the National Association for the Advancement of Colored People and the Citizen Police Review Board expressed concern about the probe's impartiality.
"We would like to see an independent investigation outside of the police department," said Connie Parker, local NAACP president. "That's like Connie Parker investigating Connie Parker."