New York City Police Commissioner William J. Bratton (left) is joined by Mayor Bill de Blasio at a news conference at Woodhull Hospital following the killing of two New York City police officers on December 20, 2014 in New York City. (Photo by Spencer Platt/Getty Images)

As details emerge about the shocking shooting deaths of two New York City police officers in Brooklyn on Saturday, they are raising questions about whether there were glitches in how information flowed between the police departments of two of the east coast's biggest cities more than a dozen years after the Sept. 11 terror attacks revealed fatal weaknesses in law enforcement's information-sharing capacities. When time was of the essence, the systems in place, technological and otherwise, did not move critical data where it was needed, in the formats in which it was needed, in time for it to be useful.

(RELATED: NYC police commissioner defends Mayor de Blasio’s handling of the officers’ shootings)

New York City Police Commissioner William J. Bratton, on Saturday night, described the shooting of the officers as happening "without warning." Indeed, the two officers who were killed had no notice they were under attack. Police in Baltimore County, though, where the eventual Brooklyn shooter, 28-year-old Isamaaiyl Brinsley, was a suspect in an early-morning shooting, have pointed out that they attempted to alert their colleagues to the north of the threat Brinsley posed -- though that perhaps represented only minutes of advance warning.

Here, the timeline is key.

Shortly before 6 a.m. on Saturday, Baltimore County Police say, they were called to the scene of a shooting in an apartment complex of a woman believed to be Brinsley's girlfriend. Brinsley took the woman's cellphone when he fled, and her mother reportedly alerted Baltimore police that Brinsley seemed to be posting threatening images to her daughter's Instagram account. Those images included the hashtag #ShootThePolice and suggested that he was going to kill police officers that very day. Baltimore County police say that they learned of those threats at 1:30 p.m.

Baltimore police tracked the cellphone to downtown Brooklyn. At 2:10 p.m., the Baltimore County Police Department says, they called a local police precinct near the phone's location to let them know both that the suspect's mobile phone was "pinging" nearby and about the Instagram threats.

At about the same time, Baltimore police say, they faxed a wanted poster for Brinsley to the New York City Police Department. The poster detailed the online threats against police, noting that he was armed with a 9mm handgun and "currently believed to be in the New York Area, possibly the Brooklyn area."

The New York City police department, however, says that the fax wasn't received until approximately 2:45 p.m. Either way, Baltimore police say that at 2:50 p.m., it sent the same information contained in the flyer to New York City's Real Time Crime Center. That center, operated by the New York City Police Foundation, collects and analyzes field data, including arrests records, warrants, mug shots. That information "once took weeks to process," says the center. Instead, it aims to transmit that insight "to investigators in the field in 'real time." Alas, this time it was too late.

"Tragically, this was essentially at the same time as our officers were being ambushed and murdered by Brinsley," Bratton said on Saturday. Indeed, by about 2:47 p.m, according to NYPD, the officers, 32-year-old Police Officer Wenjian Liu and 40-year-old Police Officer Rafael Ramos, had been shot and killed in their parked patrol car in the Bedford-Stuyvesant neighborhood of Brooklyn.

It is, of course, painful to raise questions about the police response to a shooting that took two of their own, but a full assessment of the crime would seem to cry out for an investigation into whether -- amid what is, of course, the fog of duty experienced by any big city police department -- that information could have been shared in time to allow those officers the chance to protect themselves.