After an FBI and Houston Police Department investigation determined that veteran Officer Tam Pham had participated in the deadly breach at the U.S. Capitol this month, his departure from the department was swift.
He was placed on administrative leave and resigned, with no pushback from the group that would usually advocate on behalf of an officer accused of wrongdoing.
The Houston Police Officers' Union has fiercely defended its officers, even in cases that call officer conduct into question — including one last year when officers shot and killed a man with a history of mental health issues who was on his knees.
The president of the union at the time called the firings of four officers in September "unjust and deplorable" and said the organization would represent them at their arbitration hearings.
The union's response has been markedly different in the case of Pham, who faces two federal misdemeanor charges related to entering the Capitol.
Anyone who breached the Capitol "should be charged and receive whatever punishment is assigned to that," said Douglas Griffith, who is now the union president. "No matter if they're a police officer or not."
Pham has not yet entered a plea. His attorney said Pham "is deeply saddened to be associated with the domestic terrorists who attacked our Capitol" and "believes strongly in the rule of law."
Griffith said that what separates what Pham is accused of from the charges other officers have faced in unrelated incidents is that the Capitol riot "was an attack on our democracy" that led to the death of an officer and to others' being seriously injured. Five people, including a Capitol Police officer, died in events related to the attack.
"As an officer, I would expect, if I saw some officers being attacked, I'd be stepping in between them," Griffith said in an interview. "I wouldn't be participating in that kind of activity."
Police departments in New York City, Seattle and Virginia are investigating whether their officers participated in the pro-Trump riot. As they do, police unions are confronting the dilemma of whether or not to defend officers who took part.
In Chicago, for example, the union president initially defended the mob before backing down. And in Seattle, the union head is under administrative investigation after he falsely claimed that Black Lives Matter was responsible.
Kalfani Ture, a former police officer in Georgia who is an assistant professor of criminal justice and policing at Quinnipiac University in Connecticut, said the growing number of off-duty police officers who are suspected of having taken part in the riot creates an interesting paradox for police unions, which have largely shielded bad cops from accountability.
"When we see an officer lose his life, when we see other officers injured, when you see these figures attacking other police officers, how do you justify that?" Ture asked.
Ture said police unions are breaking from their own because of the Capitol Police officer's death and the injuries sustained by dozens of other officers.
"If it wasn't for the optics, if it wasn't for the loss of life, if it wasn't for 50 police officers, both Capitol Police officers and Metropolitan Police, being injured — severely injured — to the extent that it removed them from duty, if it wasn't for all of that, I wouldn't be surprised if the various police unions" said: "No one was really hurt. It was just an exercise of their First Amendment rights that essentially got out of hand."
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John Catanzara, the president of Chicago's Fraternal Order of Police lodge, initially defended the mob that stormed the Capitol at President Donald Trump's behest.
"There was no arson. There was no burning of anything. There was no looting. There was very little destruction of property," Catanzara told WBEZ, Chicago's main public radio station, in an interview the evening of Jan. 6. "It was a bunch of pissed-off people that feel an election was stolen, somehow, some way."
Photos and video of the incident show that the rioters overwhelmed police, smashed windows of the Capitol, overturned tables and ransacked offices. A 19th-century marble bust of President Zachary Taylor was defaced with what appeared to be blood. Residue of pepper sprays, tear gas and fire extinguishers — deployed by both rioters and law enforcement officers — was also evident in the aftermath.
Catanzara, a staunch supporter of Trump, told WBEZ that he believed, as Trump has falsely claimed repeatedly, that the election was stolen, but he admitted that there is no proof. Catanzara said what rioters did was "very different than what happened all across this country all summer long in Democratic-ran cities, and nobody had a problem with that."
After it was announced that a Capitol Police officer had died, Catanzara apologized, saying he had "showed a lapse in judgment" in the WBEZ interview.
"I certainly would never justify any attacks on citizens, democracy or law enforcement," he wrote in a statement posted on Facebook.
He did not mention the officer's death, but he said that he was sorry and that "after seeing more video and the full aftermath, my comments would have been different." Catanzara, who faces calls to resign, declined a request for an interview, but he told NBC News on Thursday that he does not plan to step down.
His comments drew harsh criticism from Chicago Mayor Lori Lightfoot and Patrick Yoes, president of the National Fraternal Order of Police, who said Catanzara's remarks do no represent the opinions of its 356,000 members.
"There is no question that, in addition to the tragic loss of life, these criminals left a wide swath of damage, in the building that is the heart of our democracy and threatened our elected officials, Congressional staff as well as our brother and sister officers," Yoes said in a strongly worded statement that mentioned Officer Brian Sicknick, who died after he was hit in the head by a rioter wielding a fire extinguisher.
"The National FOP rejects this gross mischaracterization and sees the incident for what it was — a violent mob of looters and vandals, visiting fear and destruction on one of our nation's most sacred spaces," Yoes wrote.
Officer Mike Solan, president of the Seattle Police Officers Guild, faces increasing calls for his resignation from the union and the police department after he falsely suggested that Black Lives Matter activists played a role in the violence at the Capitol. At least five Seattle police officers are being investigated for possible involvement.
Mayor Jenny Durkan and former Police Chief Carmen Best have called for Solan to retract his words and apologize or resign. Solan did not respond to requests for comment.
Seattle's Office of Police Accountability is investigating Solan's tweets, including one on Jan. 8 saying the "far right and far left are responsible for that sad day," to determine whether they violated department policy.
The New York City Police Benevolent Association has decried the riot as a "despicable attack," which an unidentified officer is alleged to have participated in.
Jack Glaser, a professor at the Goldman School of Public Policy at the University of California, Berkeley, said the pro-Trump rioters "undermined or really laid bare the reality of most of these groups, which is really not about law and order but more about racial hegemony."
The union, which represents about 24,000 rank-and-file officers, endorsed Trump for re-election last year. The union did not return multiple requests for comment.
Glaser said he suspects that the rioters' "violation of basic democratic principles is enough that the unions feel like they cannot back that up."
"I think what we see here is that the violence on the part of the rioters, of the insurrectionists, in the name of the thin blue line — some of them carrying the modified American flag with the blue lines — I think that that was an offense to policing professionals and what had been seen as a supportive alliance," Glaser said. "This really stripped away the pretense of those symbols."
Ture agreed, citing the "profoundly great" contradiction between the espoused support for law enforcement and the actions at the Capitol.
He added that unions that defended officers involved in the attack would struggle to sever themselves from the images of people bearing Confederate flags and other racist insignia associated with white supremacists.
"If you had taken part in this campaign," he said, referring to the attack, "you cannot easily disassociate yourself with that type of bigoted prejudice, that evil terrorism."