Today is the 30th anniversary of the night Los Angeles police officers nearly killed 25-year-old Rodney King. On a road near the San Fernando Valley freeway, more than a dozen officers surrounded King while at least four Tasered, clubbed and kicked the young Black man until he appeared to them to be dead. They threw a sheet over his head when they were finished.

The assault on King became national news because Lake View Terrace resident George Holliday captured nine minutes of it on his camcorder. That video footage became evidence in the high-profile 1992 trial against four LAPD officers. And, of course, the juxtaposition between the horrific scenes on that videotape and the jury acquittal of the officers was a catalyst for that year’s Los Angeles riots.

But that moment between the traffic stop and the trial verdict is important. The powerful visual evidence of racism and brutality convinced Black activists and political leaders nationwide that there might finally be accountability. And it heartened survivors of police violence. Although it was a window of radical possibility that closed with extraordinary disappointment, Black activists channeled thwarted hope into the work of explaining the insidiousness of racial violence to a public that didn’t yet get it.

The LAPD had a long history of racist abuse that had accelerated under the leadership of Police Chief Daryl Gates between 1978 and 1992. The LAPD routinely deployed a six-ton tank-like battering ram and, under the banner of “Operation Hammer,” conducted spectacularly destructive raids in Black residential neighborhoods that left families homeless and drew the emergency resources of the American Red Cross. Gates spoke flippantly of Black men who died in police chokeholds, and made a statement before the U.S. Senate that casual drug users “ought to be taken out and shot.” (Later asked to clarify, he said he sure did mean it.) All the while, year after year, city council members failed to check the LAPD’s power. Facing complaints about civil rights violations, brutality and criminal misconduct, Gates and his force proved virtually untouchable.

News of the existence of video-recorded evidence reassured King as he began his painful recovery. After the savage traffic stop, he was treated in two different hospitals and moved, mercilessly, to the Los Angeles County jail, where he was held for resisting arrest. During those 72 hours, the Holliday tape began making its rounds and televised footage of the mob-like attack on King provoked national outrage, which created an incentive for the traumatized and fearful young man to go public with his injuries. Released from jail on March 6, charges dropped, King displayed for reporters his facial swelling, cuts, broken bones, grisly burns and bruises covering his stomach.

After King’s news appearance, more than a dozen eyewitnesses came forward to fill in details about what happened before Holliday began filming. Josie Morales, a 26-year-old resident of a nearby apartment complex, said she and her husband, Heriberto, watched King exit his car and immediately put his hands on the hood. She noted, “He never moved his hands.” Another tenant, 26-year old Dawn Davis, reported that even as officers yelled “Fighting!” King was immobile and “facedown.” Dorothy Gibson, a 53-year-old nurse, also described King lying prone and said she heard him crying, “Please stop, please stop.” Their descriptions of King’s efforts to cooperate directly contradicted the LAPD’s written reports citing his erratic behavior as justification for their actions.

King’s media appearances, the Holliday tape, corroborating witness statements and revelations that the officers had bragged about the beating while referring to King as a “gorilla” prompted immediate action by Los Angeles officials. Quick-fire announcements came in the week following March 3. The city’s police commissioner, Melanie Lomax, compared the LAPD’s treatment of King to something “straight out of South Africa and the Deep South.” Gates called for three of his officers to be prosecuted, and he suspended a dozen others, even as Mayor Tom Bradley, civil rights activist Jesse Jackson and then-Sen. Joe Biden all demanded his removal. District Attorney Ira Reiner promised to bring charges against all those responsible for King’s injuries, and a Los Angeles grand jury indicted four of the officers on five felony charges. The FBI also took action, opening an investigation into misconduct within the ranks of the LAPD.

The fury was palpable, and the momentum built swiftly.

Black Americans were emboldened by what they observed. Many were hopeful that such irrefutable evidence would not only ensure justice in a court of law in the case against the LAPD but that it would move White Americans to support expansive reforms to combat racist policing. In Los Angeles, leaders of the local Coalition Against Police Abuse (CAPA) understood that King was only the latest victim of extreme police brutality in Los Angeles, and luckier than Black victims like Booker Ford, James Richardson, Carlos Washington and Eula Mae Love, because he had survived it. But CAPA, like the NAACP, members of the Congressional Black Caucus and longtime police watch activists nationwide, believed the Holliday tape had flipped the script.

The mood in 1991 might be summed up best by the confidence with which rapper Ice Cube thought: “We finally got y’all … on tape.” White Americans couldn’t look away from the riveting footage. And for Black America, that was critical. The Holliday tape promised an American public primed for sweeping, institutional changes, just as it had been in 1963, when photographers in Birmingham, Ala., captured images of Black children thrashed by police commissioner Eugene “Bull” Connor’s fire hoses. Here was another egregious display of state barbarism, played on loop.

And in fact, Black leaders across the nation sought to use the case as a way to bring about systemic reform. Armed with a deep file of cases collected by the ACLU and the NAACP, the Congressional Black Caucus demonstrated that the abuse captured on film reflected an epidemic in American policing. Members called for the Justice Department to broaden the scope of its investigations of police abuse to include all urban law enforcement agencies throughout the country. “If we can’t protect citizens against the kind of videotaped violence that occurred in LA that night,” Rep. John Conyers Jr. (D-Mich.) asserted, “we’re a nation in jeopardy.”

But there were signs that the criminal justice system would not change so quickly. In November 1991, after store owner Soon Ja Du was convicted of killing 15-year-old Latasha Harlins, a Black girl —— another shooting caught on video —— the Los Angeles judge in the case defied the jury’s recommendation for Du to serve the maximum 16-year jail sentence. Instead Judge Joyce Karlin sent the convicted woman home with a $500 fine.

The legal process also undermined the political push for reforms three months later in the trial against King’s attackers. The defense managed to slow down and dissect portions of the Holliday tape to spin a narrative that King was the aggressor and the cops acted accordingly. The nearly all-White jury took less than a day to acquit the four officers in late April 1992. Then, Los Angeles erupted.

Many expected 1991 to be a landmark year in the fight for police accountability in Los Angeles and across the nation. It wasn’t. The wide dissemination of video footage of police abuse was brand-new, and it garnered an unprecedented amount of attention that ensured sympathy for victims of police abuse. But it was not enough to secure meaningful change because, as it turned out, the justice system was willful in its commitment to devaluing Black lives.

Decades later, police killings are routinely filmed. Think of Oscar Grant in Oakland, Anthony Lamar Smith in St. Louis, Eric Garner in New York, Michael Brown in Ferguson, Alton Brown in Baton Rouge, Philando Castile in suburban St. Paul and George Floyd in Minneapolis. The existence of video evidence no longer inspires much hope for police accountability. Yet there is still radical possibility in the dogged work of young Black activists today who understand that even in the absence of accountability, video continues to provide a way to make visible the grim determination of the racist systems protecting violent cops.