The killings have raised concerns and tempers in the already tense nationwide debate surrounding police conduct. Some key developments after the weekend shooting in New York:
ABOUT THE VICTIMS
Ramos, who celebrated his 40th birthday this month, joined the New York Police Department in 2012 after working as a school security officer. He was a lifelong Brooklyn resident, living in the Cypress Hills section where he grew up.
He was married with two sons: a 13-year-old who attends middle school in Brooklyn and another at Bowdoin College in Maine. The younger son, Jaden, posted on Facebook about how much Ramos meant to him.
"He was the best father I could ask for," Jaden Ramos wrote. "It's horrible that someone gets shot dead just for being a police officer. Everyone says they hate cops but they are the people that they call for help. I will always love you and I will never forget you. RIP Dad."
The 32-year-old Liu, whose family moved from China when he was a teenager, had been a member of the police force for seven years, after serving in the police auxiliary. He moved this year to a home in Brooklyn's Gravesend section and got married two months ago.
Liu's parents, from the city of Toishan in the southern Chinese province of Guangdong, are limited in their English. A police sergeant who served as an interpreter for them said a lot of Chinese families want their children to become doctors and lawyers but Liu "came here and wanted to become a police officer."
FUNERALS AND HELP FOR FAMILIES
A wake for Ramos will be held Friday at Christ Tabernacle Church in Glendale, Police Commissioner William Bratton said. Ramos' family says he was deeply religious and heavily involved in the church. The funeral will be held there Saturday.
Liu's family is traveling to the U.S. from China and will decide on arrangements after it arrives, Bratton said.
Meanwhile, U.S. Attorney General Eric Holder directed the Department of Justice to expedite death benefits to the officers' families.
CALLS FOR RESTRAINT
New York's governor, the city's mayor and others called for restraint amid the heated rhetoric surrounding the shooting of the two officers.
Mayor Bill de Blasio called Monday for a pause in protests over police conduct. He faces a widening rift with those in a grieving police force who accuse him of creating a climate of mistrust that contributed to the killings of the officers. He called for "everyone to put aside political debates, put aside protests, put aside all of the things that we will talk about in all due time."
Gov. Andrew Cuomo urged calm through the holidays and respecting families' grief. He told WNYC Radio that people are angry on both sides and that it's time to lower the rhetoric, followed by "rational, sober conversation" to consider "systemic reform."
ABOUT THE GUNMAN
Emerging details on Brinsley are clarifying a portrait of him as a mentally disturbed loner.
He was accused of firing a stolen gun into a car in an apartment complex parking lot in the Atlanta area in 2011 after a female acquaintance refused to let him inside. In a police report, the woman said she didn't know him well but her sister was friends with him.
Officers wrote that Brinsley ran when he spotted patrol cars nearing the complex, setting off a foot chase that ended when one officer used a stun gun. Officers said Brinsley wouldn't raise his right hand, keeping it near his waist after being told to put his hands in the air. Police later found a gun in a storm drain matching the bullet found in the car.
Daniel McCall, an attorney appointed to represent Brinsley, said his client took responsibility for damaging the car.
"Some people (appointed an attorney) are difficult to represent because they don't trust you or don't like the system," McCall said. "He was not hard to represent in that sense at all."
In one court document, Brinsley answered "yes" when asked whether he had been a "patient in a mental institution or under the care of a psychiatrist or psychologist." McCall said he doesn't remember any friends or relatives being involved in his client's defense or noticing any psychiatric problems at the time.
A plea deal required Brinsley to complete a boot camp followed by five years' probation. He failed to complete drug and alcohol or anger and violence evaluations or check in with probation officers.
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