(CNN) One day after George Floyd's fatal encounter with Minneapolis police on Memorial Day, the four officers involved were fired.
Four days later, one of the officers was arrested and charged with Floyd's murder. Within 10 days, the other three officers were in custody.
Since Floyd's death, officials in Minneapolis and other cities across the country have leveled criminal charges and taken decisive disciplinary action against police brass and officers whose conduct has come into question.
Whether those moves are a response to the tense, national climate or a sign of more lasting change remains to be seen.
Sam Walker, a professor of criminal justice at the University of Nebraska, Omaha, said he would not be surprised if the heat of the moment contributed to the actions of the past week.
"But how many of these cases are there around the country?" he asked. "And, even more important, how often will this occur six months from now? I am very skeptical."
Philip Stinson, a professor of criminal justice at Bowling Green State University in Ohio, cautioned against drawing conclusions from a handful of anecdotal incidents.
"Policing is very slow to change, and it seems to me that it's largely business as usual," he said.
Christy Lopez, a Georgetown Law professor and former DOJ lawyer who worked on police practice cases, said official responses to excessive or inappropriate uses of force at protests have been swift and sure in some places but non-existent in others.
"What we are seeing so far indicates to me that some police agencies are definitely doing a better job listening to, believing and supporting communities when police officers act wrongly, but other agencies appear to still be stuck in the last century on this issue," she said.
Still, David Harris, a University of Pittsburgh School of Law professor, said officials have been quicker to act against misconduct since the 2014 Ferguson, Missouri, killing of Michael Brown.
The unarmed black teenager was fatally shot by a white police officer. A grand jury did not indict Officer Darren Wilson in November 2014; Wilson later resigned from the police department.
"Now it's much more accepted and expected that when they have the evidence they will move on it," Harris said. "It's the post Ferguson era. That's when things began to change -- the awareness of a national problem, the idea people are not going to look away.
These are examples of official action taken against police brass and officers in the past week:
The Minneapolis police officer who pressed his knee into the back of Floyd's neck for nearly nine minutes was charged with third-degree murder and second-degree manslaughter four days after the killing.
The charge against Derek Chauvin was upgraded to second-degree murder on Wednesday. That same day charges of aiding and abetting second-degree murder were leveled against three other officers involved in an incident that sparked nationwide protests.
Police Chief Medaria Arradondo fired the four officers one day after the fatal police encounter that left Floyd unconscious and pinned beneath three officers, exhibiting no signs of life.
Thomas Lane and J. Alexander Kueng, who helped restrain Floyd, and Tou Thao, who stood near the others, were not initially charged.
Lane, 37, Kueng, 26, and Thao, 34, have now been charged with aiding and abetting second-degree murder and aiding and abetting second-degree manslaughter.
Chauvin, 44, is being held at the Minnesota Department of Corrections facility in Oak Park. His bail was increased to $1 million Wednesday, court documents show.
Lane, Kueng and Thao were taken into custody Wednesday and are being held on $1 million bail, county jail records show.
Louisville Metro Police Department Steve Conrad was fired Monday after officials discovered that two police officers involved in the fatal shooting of a Kentucky resident had not activated their body cameras.
"This type of institutional failure will not be tolerated," Mayor Greg Fischer said.
The officers who fired their weapons, identified as Katie Crews and Austin Allen, are on administrative leave pending multiple investigations into the shooting.
The unidentified National Guard members have not been been disciplined or reprimanded, said Steve Martin, a spokesman for the state's National Guard.
David "Yaya" McAtee's BBQ stand was a longtime fixture on the Louisville corner where he was mortally wounded. He appeared in surveillance video released by police Tuesday to fire at officers who were using pepper balls to disperse a crowd in a neighboring parking lot.
The officers appeared to take cover before returning fire early Monday.
In one video, the 53-year-old McAtee, in a red shirt, was seen at the door of the business with his right arm extended. People moved quickly farther back in the storefront. A woman shut the door. McAtee is then seen returning inside, clutching his chest and falling to the ground, according to the video.
Fischer said Wednesday the city will hire an outside company to conduct a full, independent review of the department's practices and use of force training.
McAtee was shot as police and National Guard members tried to disperse a large crowd on the street, according to police, who said officers returned fire after being fired upon. The city has a dusk-to-dawn curfew after nights of protests.
Six Atlanta police officers were charged after allegedly using excessive force during the arrest of two college students at a protest on Saturday night, according to Fulton County District Attorney Paul Howard.
The officers were filmed in downtown Atlanta breaking windows of a vehicle, yanking a woman out of the car and tasing a man.
The two victims were later identified as college students at Spelman and Morehouse, both historically black schools. They were returning from protests calling for an end to police violence against black people.
Arrest warrants named Lonnie Hood, Willie Sauls, Ivory Streeter, Mark Gardner, Armond Jones and Roland Claud. The charges include aggravated assault of Messiah Young, aggravated assault of Taniyah Pilgrim, simple battery and criminal damage to property, Howard said.
Two of the six officers, Streeter and Gardner, were terminated Sunday by Atlanta Mayor Keisha Lance Bottoms.
"As we watch the video today, it became abundantly clear immediately with the young woman that this force was excessive," Bottoms said on Sunday. "It also became abundantly clear that the officer who tased the young man needed to be terminated as well."
The officers were booked, five on felony charges, on Wednesday. All six have been released on signature bonds, according to the Fulton County Sheriff's Office.
CNN was working to contact the six men.
Atlanta Police Chief Erika Shields apologized to the students.
"How we behaved as an agency, as individuals, was unacceptable and I know that we caused further fear to you, in a space that's already so fearful for so many African Americans and I am genuinely sorry," she said.
But she expressed concern about the charges in an internal memo, saying she hadn't expected them.
Criminal charges "were never part of any discussion that I had with the Mayor or her administration," Shields wrote in the memo obtained by CNN.
"The officers were fired because I felt that is what had to occur," Shields wrote. "This does not mean for a moment that I will sit quietly by and watch our employees get swept up in the tsunami of political jockeying during an election year."
A Fort Lauderdale, Florida, police officer was relieved of duty and placed on administrative leave after a video surfaced showing him shoving a kneeling protester, Police Chief Rick Maglione announced on Monday.
The Florida Department of Law Enforcement is investigating the Sunday incident, which occurred as tensions rose during a protest downtown.
The video, taken by another protester, showed the officer, later identified as Steven Pohorence, pushing a black woman who was on her knees toward the pavement as he walked passed her.
Another officer appears to reprimand Pohorence after the shove.
Maglione said multiple officers had requested help in that area before the incident. One, he said, had her car jumped on and its windows broken while she was in it.
The police chief said the Pohorence will "remain home" until the Florida Department of Law Enforcement completes its investigation. After that, Fort Lauderdale police will conduct an administrative investigation to find whether he violated police protocol.
CNN attempted to reach Officer Pohorence through his union, the Ft. Lauderdale Fraternal Order of Police, but they declined and offered no further comment, citing the "open and on-going investigation."
An officer who posted a photo on Instagram of himself in riot gear and the caption "Let's start a riot" has been fired, according to the Denver police department.
"The Internal Affairs Investigation revealed that the officer violated the Department's social media policy, posted content inconsistent with the values of the local Department, and the officer has been terminated," the department said in a statement.
The picture was shared on social media over the weekend. The Denver Police Department announced an internal investigation on Monday. The firing of the officer, Thomas McClay, was announced on Tuesday.
Denver Mayor Michael Hancock tweeted his support for Chief Paul Pazen's decision to fire the officer. The mayor said he regretted the post occurred "at a moment in time when we must all bring out the very best of ourselves to meet the challenges before us."
"Thank you to the officers who are working to keep us all safe during this very difficult time," the mayor wrote.
Pazen joined in with demonstrators on Monday, linking arms with protestors.