Derek Chauvin sparked outrage from the moment video of his knee pressed into George Floyd’s neck for 9 12 minutes surfaced.

Chauvin, a former Minneapolis police officer convicted of murder in April, became the face of intolerance, injustice, and police brutality, sparking worldwide protests against these ills.

However, the inaction of his three coworkers who stood by while he murdered Floyd has also prompted change.

The former officers, Tou Thao, J. Alexander Kueng, and Thomas Lane — whose federal trial begins this week on charges of violating Floyd’s civil rights — has led multiple states to codify through legislation or policy that officers have a duty to step in if they witness a colleague using excessive or unauthorized force.

According to Josh Parker, a senior attorney at the Policing Project at New York University School of Law, as of October, at least 18 states required officers to intervene or required law enforcement agencies to adopt policies imposing such a duty on officers, and at least 17 states required officers to report when another officer used excessive force.

According to Parker, Illinois, Maryland, Massachusetts, and Washington are among the states that have enacted comprehensive use-of-force statutes in the aftermath of Floyd’s murder.

An Act Relative to Justice, Equity, and Accountability in Law Enforcement in the Commonwealth, enacted in Massachusetts, allows for the decertification of officers who fail to intervene “to prevent the use of excessive or prohibited force by another officer.”

In Maryland, a similar law makes it a misdemeanor offense for an officer to “knowingly and willfully” fail to stop or prevent a colleague from using excessive force, punishable by up to five years in prison and/or a $10,000 fine.

Manka Dhingra, the primary sponsor of Senate Bill 5066, which the Washington Senate passed in February, said the legislation was inspired by the deaths of people of color at the hands of police, including Floyd, 46, a Black man, who died after being restrained on the ground in the prone position.

According to evidence presented at Chauvin’s state trial, Kueng knelt on Floyd’s back while Lane held his legs down. Thao stood nearby, keeping onlookers at bay; some of them shouted at Chauvin to get off Floyd’s neck.

Thao and Kueng are accused in the federal case of failing to stop Chauvin from kneeling on Floyd and of failing to assist him. Lane, who was caught on body camera video twice asking Floyd if he should be turned on his side, is only charged with the latter count. The men will also face state charges of aiding and abetting second-degree murder in the future. Chauvin was convicted of state murder and manslaughter charges in April, and he pleaded guilty to a federal count of violating Floyd’s civil rights last month.

Dhingra described the bystander video of Floyd’s final moments as “horrible,” as well as “the officers standing around and not intervening” despite the fact that their department had a duty-to-intervene policy at the time.

Supporters argue that the measures provide states with new tools for rooting out rogue officers and holding police officers accountable to the public rather than one another.

Parker believes that if other officers had intervened, the deaths of Floyd and Eric Garner in New York — both of whom had dying pleas that included “I can’t breathe” — could have been avoided.

While Dhingra and other policing experts say it’s difficult to measure the success of such policies right now, Dhingra says Washington state “has had a decline in officer-involved shootings in the last year,” which she believes can be attributed in part to this measure.

According to Alexander Shalom, senior supervising attorney for the American Civil Liberties Union in New Jersey: “We should not be afraid of partial solutions that are still beneficial. And this, I believe, qualifies as such.”

Retired Officer De Lacy Davis believes that establishing a legal duty to intervene “is nothing more than a political reaction to failed accountability in the policing system,” and that it will not be enough to break down the so-called blue wall of silence, which prevents officers from reporting their colleagues’ wrongdoing, criminal or otherwise.