More than 100 police officers in St. Louis and Philadelphia are now either on an "exclusion list" or have been placed on administrative duty while they are being investigated for offensive social media posts.

St. Louis’ top prosecutor added 22 names Tuesday to the list of officers banned from bringing cases to her office after a national research group accused them of racist and anti-Muslim posts on social media.

The 22 new names bring the total number of officers on Circuit Attorney Kimberly Gardner's "exclusion list" to 59, roughly 5 percent of the department’s force of 1,189 commissioned officers. Only 22 of the 59 are on the list because of offensive posts.

Gardner sent a letter to Public Safety Director Jimmie Edwards and St. Louis Police Chief John Hayden on Tuesday informing them of the changes, indicating seven of the 22 officers are “permanently banned" from presenting cases for warrants. Cases currently under review, in which they are an essential witness, will be refused, Gardner said in a news release Tuesday. The other 15 will be reviewed to consider conditions of reinstatement.

"When a police officer's integrity is compromised in this manner, it compromises the entire criminal justice system and our overall ability to pursue justice," Gardner said in the release. "After careful examination of the underlying bias contained in those social media posts, we have concluded that this bias would likely influence an officer's ability to perform his or her duties in an unbiased manner."

The public safety director did not return a request for comment. The police chief's office declined comment, citing an ongoing investigation.

Jeff Roorda, business manager for the St. Louis Police Officer's Association, said Gardner's announcement is "nothing more than a grand distraction."

"The city adopted a social media policy in September 2018 and all these posts predate that," Roorda told NBC News in a phone interview Wednesday, adding that many posts precede the officers' employment with the department.

Roorda said the 22 newly added officers are being investigated for conduct unbecoming and that three of the 59 have been put on administrative duty by the police chief.

The announcement follows the disclosure this month by the Plain View Project, which studied thousands of Facebook posts from several jurisdictions around the country, including St. Louis and Philadelphia, as part of an initiative that began in 2017.

The group’s database surveyed more than 5,000 Facebook posts from 3,500 Facebook accounts of current and former officers in eight departments.

Forty-three of the 3,500 accounts viewed by the Plain View Project are tied to St. Louis. Twenty-two of those involve current officers, and 21 of them are former officers.

Some of the posts mock Muslims and Islam. Others display the Confederate flag and question whether Black History Month and the Black Lives Matter movement are racist.

In her letter to the public safety director and police chief, Gardner said that many of the social media statements and viewpoints of these current and retired officers "are shocking and beneath the dignity of someone who holds such a powerful position, especially those comments that advocate violence."

"While the St. Louis Metropolitan Police Department may be limited in their actions due to its labor agreements, the Circuit Attorney’s Office has no such privity with those contracts," Gardner said.

In Philadelphia, Police Commissioner Richard Ross said Wednesday that 72 officers have been placed on administrative duty as a result of an initial investigation into offensive social media content. Earlier this month, 10 Philadelphia cops were placed on administrative duty as internal affairs investigated whether any of their posted content violated the department's social media policy, which states, in part, employees “are prohibited from using ethnic slurs, profanity, personal insults; material that is harassing, defamatory, fraudulent, or discriminatory.”

“We are trying to deal with some of the worst postings first,” Ross said at a news conference. "Internal affairs has identified and prioritized the posts clearly advocating violence or death against any protected class, such as ethnicity, national origins, sex, religion and race."

Ross said the investigation into the 3,100-plus questionable posts would be conducted in stages by the Philadelphia Police Department's internal affairs bureau and a local law firm hired by the city.

The law firm will evaluate each post to determine whether it is constitutionally protected, he said.

“If the speech is protected, no further action will be taken,” Ross said. “If the speech is not protected by the First Amendment, there will be discipline."

He also expressed disappointment.

“We’ve talked about from the outset how disturbing, how disappointing and upsetting these posts are and how they will undeniably impact police-community relations," Ross said. "We’re not naïve to the fact and nor are we dismissive of it."

Chris Burbank, vice president of strategic partnerships for the Center for Policing Equity, a research organization in New York City, said police chiefs have a responsibility to protect the integrity of the profession against the damage that could come from some officers' poor behavior.

"There are good officers who are not engaging in that behavior and are valuable members of the community," Burbank, a former police chief in Salt Lake City, said. "By turning a blind eye, you are eroding the trust in the good people who do not engage in that behavior."

Burbank also said police officers should be held to a higher standard than the public and that biased or offensive social media posts can call into question an officer's ability to be impartial.

"It may well be protected speech. They have a right to say that," Burbank said of officers' social media posts. "But it does not entitle you to say whatever you want and be a police officer. "