A Mesa police spokesman said Tuesday that the FBI notified the Mesa Police Department that it will not investigate the shooting of a 28-year-old U.S. Army veteran who was killed by three officers last year.

Det. Nik Rasheta said in an email that the police department received a letter from the FBI on Tuesday. "Basically, they declined to investigate," Rasheta said. He said it was unlikely that he could release the letter to The Arizona Republic because it was the end of the business day.

The fatal shooting was one of four cases under review by the FBI to determine if Mesa police officers violated people's civil rights when they used force against them. FBI inquiries into two excessive-force allegations and a fatal shooting in 2016 are still open.

Mesa Police Department has been under a microscope following a number of videos either posted online or released by police that depict officers using violence.

Word that the FBI has declined to investigate the fatal shooting of Scott Farnsworth comes two months after The Republic obtained a letter the FBI sent to Mesa police asking for records related to two other use-of-force cases investigated by Scottsdale police for any criminal wrongdoing. Scottsdale forwarded the cases to the Maricopa County Attorney's Office for review, and prosecutors declined to file charges against the officers.

The FBI didn't respond to an email from The Arizona Republic seeking comment Tuesday.

Farnsworth shooting

In March, the county attorney said that Mesa police officers Robert Ravago, Shawn Kurian and Katrina Teer would not be charged with any crimes for killing Farnsworth.

On the night of Sept. 22, 2017, Mesa police responded to a report of a man waving or pointing a gun at people near Skyline High School, on Crismon Road near Southern Avenue. A football game had just ended there.

According to a police report, Farnsworth pointed a handgun at officers after they had told him to drop the weapon. The three officers fired at least 11 times in all, based on the casings that investigators collected from Kurian's AR-15 rifle and the Glocks used by Teer and Ravago, the report says.

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After the shooting, Teer and a fourth officer fired bean bags at Farnsworth. Then, a K9 officer released his dog, named Cash, to bite Farnsworth as he lay unresponsive on the ground, according to the police report.

Other officers who witnessed the bean-bag shooting and the dog said the measures were necessary: it appeared he was still holding a gun and it was not clear that he was dead, according to the report.

Other cases under FBI review

The Aug. 28 letter from the FBI concerns two excessive-force cases involving the May arrests of 35-year-old Robert Johnson, whose charges have since been dismissed, and 15-year-old Gabriel Ramirez, who was arrested on suspicion of aggravated assault and is being prosecuted as an adult.

Rasheta, the Mesa police spokesman, has said those cases are still under internal investigation.

According to the Justice Department letter obtained by The Republic, the FBI was informed of "an alleged civil rights violation" in the arrests of Johnson and Ramirez.

In the letter, the FBI requests that the Mesa Police Department turn over files, reports, notes, memos, letters and police on-body camera footage of the two cases.

Another case that is under FBI review involves the 2016 death of Daniel Shaver, who was on his knees and begging for his life in a Mesa hotel when he was shot dead by then-Mesa police Officer Philip Brailsford, who was tried for murder and found not guilty by a jury.

Rasheta said Mesa police have not received an update on the status of the other cases under review by the FBI.

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