Glimmers of hope have emerged for Americans demanding action on police violence and systemic racism in the aftermath of the death of George Floyd, the black man who gasped for air beneath the knee of a white Minneapolis police officer last month.

All four officers involved have been fired and charged in his death, a far more rapid show of accountability than has followed similar killings of unarmed black people. Massive, diverse crowds have filled streets nationwide, sometimes with politicians and law enforcement officials marching and kneeling alongside. Legislation banning chokeholds and other forms of force have been passed by local governments. And on Monday, congressional Democrats plan to roll out a sweeping package of police reforms on Capitol Hill.

But there are signs that Floyd’s killing might not be the watershed moment that civil rights advocates are hoping for, some experts say.

The extraordinary facts of the May 25 incident — the gradual loss of consciousness of a handcuffed man who cried out for his deceased mother with his final breaths — distinguishes it from the more common and more ambiguous fatal police encounters that lead to debate over whether use of force was justified. And the politics of police reform that have squashed previous efforts still loom: powerful unions, legal immunity for police and intractable implicit biases.

“We have 400 years of history of policing that tell me things tend not to change,” said Lorenzo Boyd, director of the Center for Advanced Policing at the University of New Haven. “It’s a breaking point right now, just like Trayvon Martin was a breaking point, just like Michael Brown was a breaking point. But the question is: Where do we go from here?”

It’s a familiar question for Gwen Carr, who watched her son take his final breaths on video as a New York police officer held him in a chokehold and he pleaded, “I can’t breathe.”

Thousands of Americans filled the streets for Eric Garner in 2014 — mostly black men and women — with bull horns and protest signs in dozens of cities.

But their pleas for comprehensive police reforms took hold in only a smattering of the country’s more than 18,000 police departments. Dozens of agencies adopted training on de-escalating tense encounters. Sixteen states passed stricter requirements for use of deadly force.

Not a single piece of federal legislation passed on Capitol Hill.

So when Carr reached out last week to the family of 46-year-old Floyd, who uttered the same words as her son while officers held him down, she offered encouragement — and a warning.

“I told them, ‘Don’t think it’s going to be a slam dunk,’ ” Carr said. “They had video of my son, too; the world also saw him murdered. It should have been a slam dunk then — it’s been anything but.”

Changing perspectives

There are some signs that this time is different. For one thing, public perception of police bias has started to shift. Last week, a poll by Monmouth University found that 57 percent of Americans now say police in difficult situations are more likely to use excessive force against black people. That’s a substantial jump from the 34 percent of registered voters who said the same when asked a similar question after the fatal police shooting of Alton Sterling in Baton Rouge in 2016.

Civil rights leaders and allied lawmakers point to substantial differences in protest crowds this time around: Their historic size, even during a pandemic. The faces, now as likely to be white and brown as they are to be black. After Garner’s death, there were about 50 demonstrations, compared with more than 450 so far this time around, based on media coverage and police records.

“I don’t think they used to think there was an attack on black lives. Not until it was recorded and people were seeing it, I don’t think they believed it,” said Lezley Mc­Spadden, mother of Michael Brown, who was killed by a Ferguson, Mo., police officer in 2014. “What is happening now is not new to those of us who live in these oppressed areas and communities that are devalued. But it’s new for people who don’t live in those areas. It’s changing people’s perspective.”

Even some Republican lawmakers have broken from strict law-and-order stances to express support for protesters. Last week, Sen. Roy Blunt (R-Mo.) said, “I think people are understanding that those protests make sense.” And Sen. Lindsey O. Graham (R-S.C.), chairman of the Senate Judiciary Committee and a staunch Trump ally, allowed that “there’s a problem here, and we have to get to the bottom of it.”

The growing assortment of voices represents an important shift, said Sen. Cory Booker (D-N.J.). He is among the sponsors of the Justice in Policing Act, expected to roll out Monday. The massive package targets racial profiling, bans chokeholds and no-knock warrants, and makes it easier to prosecute and sue for police misconduct.

“No change in America that is worth it has been easy. But the demands are now coming from increasingly diverse coalitions,” Booker said. “I feel we are in a moment now.”

'The deeper problem'

Reform advocates have won other victories. Last week, the Minneapolis City Council unanimously passed a ban on chokeholds and neck restraints. And the council in New York is poised to pass a law this month that would make using a chokehold in an arrest a misdemeanor.

Without systemic change, however, some experts say these piecemeal policies would do little to curb the use of excessive force and racial inequities in policing. And the effectiveness of policy changes is blunted by police union contracts that protect officers from discipline and firing for wayward behavior.

“There are so many terms and conditions in the collective bargaining agreements that insulate police from accountability and transparency,” said Jody Armour, a law professor at the University of Southern California. “Can we know who the bad police are? Are there public records? A lot of times, that is squelched in collective bargaining.”

Even changes to training can have little effect. A growing number of police departments are providing cadets with de-escalation and anti-bias training, but once they are assigned to a field training officer — a veteran on the force — the training can fall by the wayside, according to police training experts.

One of the rookie officers who helped hold Floyd down questioned whether they should roll the gasping man over, but then-officer Derek Chauvin dismissed the suggestion and insisted on “staying put” with his knee on Floyd’s neck, according to court records.

“Seasoned officers will push away from what they learned in the academy and go to what works for them in the street,” Boyd said. “And officers will often say, ‘We have to police people differently because force is all they understand.’”

Those views appear to disproportionately impact black communities, at least in the most extreme cases. A Washington Post database that tracks fatal police shootings found that about 1,000 people have been killed by police gunfire every year since 2015. So far this year, 463 people have been fatally shot. While the vast majority are white men armed with weapons, black men are killed at a rate that far outstrips their numbers in the overall population.

Other forms of police violence, from chokeholds to beatings in custody, also tend to fall heavily on African Americans, Armour said.

“When you give police discretion to enforce any law, it seems to get disproportionately enforced against black folk. Whether it’s curfew, social distancing,” said Armour, noting that Floyd was accused of using a counterfeit $20 bill.

“Would you have put your knee on a white guy’s neck like that? Would you have a little more recognition of humanity, and when he’s screaming out, ‘I can’t breathe,’ would that have raised more concern?” he said. “That’s the deeper problem.”

The vast majority of such cases are not caught on video and therefore often go unnoticed, Boyd said. For example, Breonna Taylor, the 26-year-old emergency room technician who was shot at least eight times inside her home by Louisville police in March, is often left out of the discussion of systemic injustice — in part because no one was there to record Taylor getting shot by officers serving a drug warrant, said Andra Gillespie, director of the James Weldon Johnson Institute at Emory University. All three remain on administrative leave, but no charges have been filed, according to the Courier Journal.

“Video is certainly aiding in getting justice for these individual people,” Gillespie said. “Breonna Taylor hasn’t gotten comparable attention because there is no video. That’s also because she’s a woman, and we forget the black women are subject to disproportional police violence as well.”

Even killings captured on video rarely lead to prosecution of police officers. Sterling had a handgun in his pocket when he was tackled by police outside a Baton Rouge convenience store, and police said he was reaching for it when officers shot him six times. The DOJ and Louisiana attorney general decided not to file criminal charges against the officers involved. Attorneys for the officer who put Garner, 43, in a chokehold argued that he probably died because he was obese and had resisted arrest. Daniel Pantaleo lost his job after a disciplinary hearing four years later, but the Justice Department declined to bring criminal charges.

Floyd’s killing has received near-universal condemnation because it lacks the contradictory evidence that allows skeptics to deny that race was a factor in police behavior, said Armour, author of “Negrophobia and Reasonable Racism: The Hidden Costs of Being Black in America.”

“It’s almost like you have a case that’s so cry-out-loud bad that people who aren’t necessarily that sympathetic to black equality are able to come out and now make a big display,” Armour said. “It’s not that often you run into these knockdown, no-question videos.”

Setting a different tone

That raises the question of whether the nation is experiencing a real turning point or simply responding to a particularly egregious offense, some experts say.

There have been many questionable displays of solidarity: When the Washington Redskins joined the #BlackoutTuesday protest by posting a black square on Twitter, critics noted the perceived hypocrisy from an organization whose team name is a slur for Native Americans. And as New York Police Commissioner Dermot Shea celebrated images of officers embracing peaceful protesters, video surfaced Wednesday that showed his officers beating a cyclist with batons in the street.

“We’ve seen officers kneeling in the same departments that are brutalizing journalists and protesters,” said Philip Atiba Goff, director of the Center for Policing Equity research center. “You can’t say justice for George Floyd, that you condemn the actions, while you condone the actions in your own house.”

Charles H. Ramsey, a former chief in the District and Philadelphia and co-chair of President Barack Obama’s Task Force on 21st Century Policing, said perhaps the biggest obstacle to nationwide change is the unwieldy way in which police departments are organized. With every city, town, state and county fielding its own force, he said, it’s hard to standardize training and policies.

“Regionalizing them would be a solid first step,” Ramsey said. “But then you get into the politics. Every county and every mayor; they want their own police force, they want their own chief.”

For that reason, a coalition of nearly 400 disparate organizations is focusing on securing federal reforms. Last week, the group — including the NAACP, the Center for Reproductive Rights and the American Music Therapy Association — sent a joint letter to congressional leaders calling for legislation to combat police violence.

“With so many police departments, it is important that there is federal action,” said Vanita Gupta, a former head of the U.S. Department of Justice’s Civil Rights Division and CEO of the Leadership Conference on Civil and Human Rights.

Although past efforts at policing reforms stalled in Congress, Booker expressed optimism, noting that civil rights legislation has always traveled a bumpy road. Bills were introduced and stagnated for years before the Civil Rights Act passed in 1964 and the Voting Rights Act passed in 1965, he said.

Police reform advocates are skeptical. Ramsey noted that the playbook for reform that he created as chair of Obama’s policing commission sat on a shelf, unused, for five years. Meanwhile, the FBI still hasn’t followed through on a pledge to aggressively track the nation’s fatal police shootings.

“It’s been five years since they promised to fix that database,” Ramsey said. “Come on. That’s enough time.”

Julie Tate, Steven Rich, Alice Crites and Derek Hawkins contributed to this report.