On December 20, 2014, Ismaaiyl Abdullah Brinsley shot and killed Rafael Ramos and Wenjian Liu — two on-duty New York City Police Department (NYPD) officers — in the Bedford–Stuyvesant neighborhood of Brooklyn. Brinsley then fled into the New York City Subway, where he killed himself. Earlier in the day, before he killed Ramos and Liu, Brinsley had shot and wounded his ex-girlfriend Shaneka Thompson in Baltimore after initially pointing the gun at his own head.

The shooting occurred just weeks after a grand jury decided not to indict NYPD officer Daniel Pantaleo, who was responsible for the death of Eric Garner on July 17, 2014. The grand jury's decision resulted in widespread protests in New York City and across the nation against police brutality and the lack of accountability for it. The protests also coincided with widespread protests in response to a grand jury's decision not to indict Darren Wilson, the police officer who shot Michael Brown in Ferguson, Missouri, on August 9. Brinsley's motive to kill the NYPD officers was motivated by outrage over the two deaths.

Before Brinsley arrived in Brooklyn by bus, he shot and seriously wounded his 29-year-old ex-girlfriend, Shaneka Nicole Thompson, in the Baltimore suburb of Owings Mills, Maryland, on Saturday morning. The second shooting occurred at Myrtle Avenue and Tompkins Avenue, a busy intersection in Brooklyn near the Tompkins Houses. Brinsley approached the passenger window of an NYPD patrol car occupied by Rafael Ramos, 40, and Wenjian Liu, 32, of Brooklyn's 84th Precinct. He then fired a semiautomatic handgun four times through the open window, striking Ramos and Liu in the head and upper body, killing both officers instantly. Two Con Ed workers who witnessed the shooting notified police. After NYPD officers responding to the scene chased him onto the subway, he killed himself with the handgun in the Myrtle–Willoughby Avenues (G train) subway station, according to police. Brinsley and the two police officers were taken to Woodhull Hospital, and all were pronounced dead on arrival.

Rafael Ramos (December 9, 1974 – December 20, 2014), married and a father of two, resident of Glendale, Queens, had joined the NYPD as a school safety agent, before being promoted to officer in January 2012. He was active in his church, Christ Tabernacle in Glendale, and had once studied at a seminary. He had just completed a training course to become a volunteer chaplain. He planned to eventually join the ministry when he retired from the police force.

The Silver Shield Foundation, founded by the late New York Yankees owner George Steinbrenner, announced it would pay for the education of Ramos' 13-year-old son, Jaden. Bowdoin College said it would provide full financial aid to Ramos' elder son, who is a sophomore at the school, so he could complete his education.

A funeral service for both Officers Ramos and Liu, the largest police funeral in the city's history, was held on December 27 in Glendale with over 100,000 people present, including many politicians such as Vice President Joe Biden. The service was almost five hours long and was broadcast around the world, with many people coming from across the country to pay their respects to the slain officers. Afterward, Ramos' body was transported to St. John Cemetery in nearby Middle Village, where he was laid to rest. Hundreds of officers turned their backs to Mayor Bill de Blasio as he delivered his eulogy.

Wenjian Liu (simplified Chinese: 刘文健; traditional Chinese: 劉文健; pinyin: Liú Wénjiàn; April 8, 1982 – December 20, 2014) was the only son of Chinese immigrants Weitang Liu and Xiuyan Li. He and his family came to the United States from Taishan, Guangdong in China, when he was 12 years old. He was a seven-year veteran officer of the NYPD who had married Peixia Chen in October 2014. He had no children at the time of his death.

Following a wake on January 3 containing elements of Chinese and Buddhist rituals, a funeral service for Liu took place on January 4 at the Ralph Aievoli & Son Funeral Home in Dyker Heights, Brooklyn. In protest of de Blasio's perceived lack of support for them, some attending police officers turned their backs on the video screen showing de Blasio's eulogy speech; however, de Blasio and NYPD Commissioner Bill Bratton were also saluted at the ceremony. Afterward, Liu's body was transported to Cypress Hills Cemetery in Cypress Hills, Brooklyn, and was laid to rest. After his burial, a post burial dinner, a Chinese tradition for honoring the deceased and giving his spirit a good send-off to heaven, was held in Sunset Park, Brooklyn.

According to articles from NBC News, New York Daily News, and Global News, on the night that Liu died, at the request of Chen, his widow, and with the approval of his family members, doctors retrieved and collected his semen for preservation to allow Chen the chance to conceive a child belonging to her and Liu. After being artificially inseminated, Chen successfully became pregnant and, in July 2017, gave birth to a girl named Angelina. In late 2021, Chen attempted to use her late husband's NYPD benefits plan to file for Child Survivor Benefits with the Social Security Administration for their daughter, but was initially denied twice due to an outdated legal definition of the term "biological parents"; moreover, the denial claim stated that Liu did not provide a signed consent with two witnesses to provide permission to use his sperm for conceiving a child. These hurdles were finally removed when Senator Andrew Gounardes, with the help of New York Governor Kathy Hochul, stepped in and had the law amended to recognize the validity of a child's biological parents having conceived him or her through in vitro fertilisation, and in the end, Chen was able to claim Child Survivor Benefits for her daughter.

Ismaaiyl Abdullah Brinsley (October 31, 1986 – December 20, 2014) had a long criminal record and was estranged from his family prior to the shooting. He was born in Brooklyn. He had an arrest record for weapons possession and robbery, which amounted to a total of 19 arrests in Georgia and Ohio. He was convicted of felony gun possession in Georgia, where he was living at the time of the shooting. Brinsley allegedly had ties to the Black Guerrilla Family, a prison gang that was reportedly planning revenge attacks on police officers according to police informants, and the Nuwaubian Nation, a black-supremacist cult originating in Georgia. But an unnamed federal law enforcement source has been quoted as saying there were no apparent ties. Daniel McCall, who was appointed to represent Brinsley in Georgia, said Brinsley was not difficult to represent and that no psychiatric problems were noticed at that time.

On the day of the attack, Brinsley had tried to commit suicide with his gun before killing the police officers, but he was talked out of it by his girlfriend, Shaneka Nicole Thompson, whom he then shot. Brinsley also attempted suicide a year previously. After the shooting, Brinsley reportedly called Thompson's mother and other family members and claimed the shooting was an accident. Brinsley wrote on his Instagram account of his intentions to kill police as retribution for the recent deaths of Michael Brown and Eric Garner. In the post, which he made later that day while on a bus to New York City, he wrote, "I'm putting Wings on Pigs Today ... They Take 1 of Ours ... Lets Take 2 of Theirs. [sic]" By then, the Baltimore County Police Department had been tracking Brinsley's movements from Baltimore to New York City, and sent a fax to the NYPD about his intentions just a minute before the killings occurred.

U.S. President Barack Obama stated, "I unconditionally condemn today's murder of two police officers in New York City. Two brave men won't be going home to their loved ones tonight, and for that, there is no justification. The officers who serve and protect our communities risk their own safety for ours every single day — and they deserve our respect and gratitude every single day. Tonight, I ask people to reject violence and words that harm, and turn to words that heal — prayer, patient dialogue, and sympathy for the friends and family of the fallen."

Brooklyn Borough President Eric Adams, a former police officer, said, "Those who were calling for police reform were not calling for police retribution... blood is not on the hands of the mayor."

Former New York Governor George Pataki blamed current officials. He tweeted, "Sickened by these barbaric acts, which sadly are a predictable outcome of divisive anti-cop rhetoric of Eric Holder and Mayor de Blasio." The former Mayor, Rudolph Giuliani, responded that this was untrue and categorized this rhetoric as an overreaction.

Former New York City Mayor Rudolph Giuliani accused Obama of creating a hostile environment toward the police, stating: "We've had four months of propaganda starting with the President, that everybody should hate the police. I don't care how you want to describe it, that's what those protests are all about."

As Mayor Bill de Blasio and his entourage walked through the third-floor corridor of Woodhull Hospital, where the two police officers had been pronounced dead hours earlier, dozens of NYPD police silently turned their backs on the mayor in protest for his perceived lack of support for them. Earlier, de Blasio had approached a group of cops in the hospital and told them, "We're all in this together." In response, one officer said, "No we're not."

The president of the police union group Patrolmen's Benevolent Association, Patrick J. Lynch, blamed de Blasio and the protesters of the grand jury dismissal in the Garner case for inciting hostility toward the NYPD. He said, "There's blood on many hands tonight. Those that incited violence on the street in the guise of protest, that tried to tear down what New York City police officers did every day. We tried to warn it must not go on, it shouldn't be tolerated. That blood on the hands starts at the steps of City Hall in the office of the mayor."

Fraternal Order of Police President Chuck Canterbury asked Congress to consider making crimes against police officers fall under the category of hate crimes. He said, "My thoughts and prayers over the past few weeks have been with the families of officers who were, with malice and forethought, gunned down just because they served as police officers."

Protest organizer Charles Wade said about civil rights groups, "We've all said that this is a horrible thing that shouldn't have happened. I say time and time again that I'm against police violence, and I'm not against police officers in general. I have an issue with improper policing, police violence and police impunity." Reverend Al Sharpton said, "From the beginning, we have stressed that this is a pursuit of justice to make the system work fairly for everyone. This is not about trying to take things into our own hands. That does not solve the problem of police brutality."

The National Association for the Advancement of Colored People issued a statement condemning the murders.

Pastor Michael A. Walrond Jr. of the First Corinthian Baptist Church in Harlem, said, "This tragic moment may be an opportunity for people to understand each other. The pain of a mother whose son lay dead on the ground is the same pain of a 13-year-old boy who lost his police officer father. My hope is that this will shock people into coming together."

According to The Daily Beast, some bystanders at the crime scene reportedly cheered and expressed their support for the attack.

Many rappers, such as Azealia Banks, and Lecrae, also posted to Twitter, denouncing the murder-suicide.

Rapper The Game tweeted, "I guess y'all 'can't breathe' either", resulting in backlash.

Bob McManus, a columnist for the New York Post, criticized government officials for failing to condemn the blood-lust of protesters who demanded "dead cops" in retaliation for the death of Eric Garner. While not blaming the shooting on political leaders, an editorial in The Wall Street Journal argued that political leaders failed to respond to the protesters' chant—"What do we want? Dead cops."—and that such a failure "contributed to a public climate of suspicion and hate against police in which a man like Ismaaiyl Brinsley can in his deranged mind think it is justified to stalk and execute two cops on the beat." Newsday defended New York City Mayor de Blasio, saying he did not create the animosity towards the police, which is long standing in some quarters; the editorial pointed out that the Mayor spoke out against previous physical attacks on police officers by protesters.

As a result of the protest movement, there have also been calls to reform or abolish the grand jury process.

Jaden Ramos, son of Officer Ramos, posted on Facebook, "Today I had to say bye to my father. He was [there] for me every day of my life, he was the best father I could ask for. 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."

Richard Gonzales, a cousin of Ramos, urged citizens to come together and forgive the shooter.

On December 22, de Blasio asked that anti-police protestors "suspend demonstrations." Earlier in the day, NYPD Commissioner William Bratton said the killings were a "direct spinoff of this issue [of the protests]". Some protesters issued blanket condemnations of the police as "racists and worse" according to The New York Times. While the investigations into Brinsley's motivation continues, Bratton has concluded that "the protests served as an inspiration for the disturbed man."

Six people were arrested for making terrorist threats against NYPD officers in the week following the shooting. After a police union directive in December 2014, police were ordered to send two cars in response to every call. This resulted in a lack of police resources, and as a result, a 94 percent drop in summonses for minor offenses and a 66 percent reduction in arrests.

In April 2016, officers Angelo Pampena and Robert Carbone were charged with the retaliatory beating of mail carrier Karim Baker, who unwittingly provided Brinsley with directions. The beating was alleged to have occurred when the officers approached Baker in October 2015; according to the Queens district attorney, Baker was seated in his car when the officers punched and kicked him multiple times and dragged him from his car. Baker's lawyer said Baker sustained injuries to his spine, knee and face, causing Baker to be unable to return to work. Pampena stated in a criminal court complaint that the officers approached Baker because he had parked his car directly in front of a fire hydrant, but surveillance video footage showed Baker's car parked more than 15 feet away from the fire hydrant. There were audio recordings of the encounter based on calls to 911 from Baker's cellphone during the time. The criminal case against Baker was dropped with the file sealed. In March 2017, they were found not guilty of all charges by judge Michael Aloise, and their case was sealed. However, a lawsuit filed by Baker was settled for $1.5 million in October 2019.

• Shooting of Brian Moore
• Murder of Darren Goforth
• Shooting of Jesse Hartnett
• 2014 Las Vegas shootings
• 2016 shooting of Dallas police officers
• 2016 shooting of Baton Rouge police officers
• Murders of Alison Parker and Adam Ward