The Los Angeles County sheriff said on Tuesday that he was investigating a reporter at The Los Angeles Times who had reported allegations that he was involved in covering up a case of inmate abuse, an announcement that drew accusations that he was violating the reporter's First Amendment rights.

The officer accused the sheriff of blocking an investigation into the incident and retaliating against whistle-blowers in an article published by the reporter on Monday.

Ms. Tchekmedyian also published security video footage of the incident in which a police deputy handcuffed an inmates who had punched him in the face. The officer kept his knee on the prisoner's head for three minutes.

At a news conference on Tuesday, the sheriff said he was investigating all parties involved in the leaked video, which he said was stolen property.

It is a huge area of law and freedom of the press that the L.A. Times uses.

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The executive editor of The Los Angeles Times said in a statement that Alex Villanueva's First Amendment rights were violated when he reported on a video that showed a deputy.

The attempt to criminalize news reporting goes against well-established constitutional law.

The investigation of a journalist because of her reporting violated the First Amendment, according to the deputy executive director of the Reporters Committee for Freedom of the Press.

The publication of information about an alleged law enforcement cover-up that sought to block an investigation into the use of excessive force is clearly in the public interest.

Los Angeles County officials didn't charge the prisoner because they were worried that the incident would be seen as similar to the murder of George Floyd.

Ms. Tchekmedyian wrote an article on Monday that implicated Sheriff Villanueva in the cover-up.

At the news conference on Tuesday, Sheriff Villanueva denied the cover-up claims and said that he was investigating the leak of the video.

Other agencies will be thoroughly investigating this and monitoring what we are doing. The appropriate prosecutorial agencies will make a determination after it is handed over.

The Los Angeles County Sheriff's Department said in an email on Tuesday that it was unable to comment further due to several ongoing investigations, including a criminal investigation.

The department said that the sheriff is committed to transparency and accountability.