An attorney for Alton Sterling's family revealed Tuesday that former Baton Rouge police officer Blane Salamoni was called "borderline nuts" by a BRPD official in an internal email after Salamoni got into an argument with another officer — a year before he fatally shot Sterling.

Attorney L. Chris Stewart said that admission by a supervisor within the Baton Rouge Police Department, which was shared with other managers, exemplifies a larger problem in how the city responds to troubled cops and how it conducts training.

"What we’ve realized even further is this was not just the act of a rogue cop, Blane Salamoni, this was a systematic failure by the police department and also those that oversee the police department," Stewart said Tuesday morning. "One year later, this 'borderline nuts' — using the language of BRPD — officer, shot and killed Alton Sterling. ... Why was this 'borderline nuts' officer, according to BRPD, allowed to be on the streets?"

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The email Stewart referenced was sent on July 21, 2015 after a firearms training session, where Firearms Training Unit Commander Sgt. Robert Knight said Salamoni and another officer got into a "pretty heated argument," the email says.

"I had to get between them and get them in the range office," Knight wrote in the email to J.D. Leach, the former director of training at BRPD. "I got them to apologize to each other after I read the riot act. Both of them are borderline nuts. I will call you in the morning to give you the full report, but no punches thrown and they shook hands at the end."

Stewart is on a team of lawyers representing Sterling's five children in a wrongful death lawsuit against the police department and its leaders, the city and its leaders, and officers Salamoni and Howie Lake III, who were both involved in the 2016 fatal shooting of Sterling. The lawsuit was filed in June 2017.

Attorneys met for a status conference on the case Tuesday morning, where state District Judge Micheal Caldwell set the trial date for April 20, 2020.

But Salamoni's defense attorney said Tuesday that the email comment was blown out of proportion by Sterling's lawyers.

"On that particular day, Blane was in charge at the firing range and this other officer made a violation of the safety rules, and Blane did admonish him," said John McLindon, Salamoni's attorney in the criminal cases against the former officer, but not this civil case. "The other officer yelled back and they had a brief shouting match. ... It was really nothing, but officers shook hands and it was a misunderstanding."

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Salamoni was a range safety officer on that day in 2015, McLindon said. He said the other officer, Jeremy Polozola, moved at the wrong time while the group of officers were lined up shooting, which he called a "clear safety violation."

McLindon said Salamoni never faced any internal discipline for the incident.

"I don't think it's a general characterization of Blane Salamoni," McLindon said of the 'borderline nuts' comment. However, he did say that the incident was used at the closed-door termination hearing for Salamoni in March, at which Knight testified to department leaders about the incident and stood by his remarks.

On July 5, 2016 officers Salamoni and Lake, both white, responded to a call about a man selling CDs outside of a convenience store on North Foster Drive who threatened someone with a gun. They attempted to arrest Sterling, a 37-year-old black man who fit the description for the suspect. After a brief struggle with the officers that lasted less than 90 seconds, Salamoni fired his weapon multiple times at Sterling, killing him.

Afterwards, officers found a loaded handgun in Sterling's pocket. Portions of the encounter were caught on cell phone video, spreading quickly over social media and sparking nationwide protests. Louisiana governor John Bel Edwards called in federal officials to investigate the incident.

After an almost year-long investigation in May 2017, the Department of Justice declined to pursue federal civil rights charges against the officers involved in the fatal shooting of Sterling.

Attorney General Jeff Landry announced in March thathe would not file state criminal charges against Salamoni or Lake. Baton Rouge police administrators fired Salamoni about a week later for violating department policy. Lake was suspended for three days. Both officers have appealed those decisions to the Municipal Police and Fire Civil Service Board, which will hear their cases this fall.

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Salamoni has also been charged with simple battery in an unrelated case in which he is accused of slapping a suspect during an arrest. That case remains ongoing.

"Many of us didn’t feel like we had a proper resolution from the federal government, many of us didn’t feel like we got a proper resolution from the state attorney general," said attorney Michael Adams, another attorney representing Sterling's children. "Here’s a chance for us to really get in and look at the conduct of these officers and get a civil jury to decide these officers were wrong."

Adams said that the email is an example of how the Baton Rouge police department's leadership was aware of Salamoni's deficiencies in training, yet took no action.

The Sterling family attorneys said they are open to a settlement with the city, but want it to include both financial compensation for the children who lost their father as well as concrete changes within the capital city's police department.

"It has to be about reform so that this doesn’t happen again to anyone else," Stewart said.

He said they plan to find out what police department leaders, city council members and mayoral administrations knew about Salamoni before the Sterling shooting, and why no action was taken to keep an officer like him off the street.

He also said they will look into how Salamoni's parents, both current or former high-ranking officials at BRPD, might have influenced any decisions.

Steve Carleton, who is representing Salamoni in the civil lawsuit, could not be immediately reached for comment Tuesday.