A San Diego deputy responsible for two deadly shootings over the course of one year is now facing the first lawsuit against him.

In court documents, the family of Sergio Weick, a father shot and killed in August 2016 by San Diego County Sheriff's Department (SDSO) deputies Christopher Villanueva and Peter Myers, claims Weick's death was a violation of constitutional rights.

"This use of deadly force was 'excessive and unreasonable under the circumstances,'" the lawsuit states.

The documents also state that Weick's family has been deprived of the lifelong love, companionship, comfort, support, society, and care of Weick.

Villanueva is the focus of the lawsuit, but Myers is also named in the documents.

According to the San Diego County Medical Examiner's (ME) office, Weick was shot 18 times in the encounter with the deputies on Aug. 11, 2016, in Vista.

The SDSO said deputies spotted Weick driving a Lexus near the intersection of North Santa Fe Avenue and Knapp Drive and recognized him as a known gang member who had an active felony warrant for his arrest.

Investigators said Weick refused to pull over for the deputies, leading them on an 8-minute pursuit that ended in a townhome complex in the 100 block of Bronze Way.

It’s still unclear exactly what happened next.

Authorities said Weick crashed the car, hopped out, and continued fleeing from the deputies on foot.

"At some point along the narrow walkway, the suspect and deputies became involved in a confrontation,” the original press release from the SDSO stated. "During that confrontation, two deputies fired multiple rounds, striking the suspect several times.”

Weick went to the hospital in critical condition and later died.

Homicide investigators said the autopsy report showed his cause of death was "trauma from multiple gunshot wounds."

“He didn't deserve to get shot down like he didn't matter because he does,” Weick's cousin, Johnny Hoyt said.

Myers is an 8-year veteran of the SDSO, while Villanueva had been with the SDSO for two months before the shooting of Weick.

Prior to joining the SDSO, Villanueva had been a police officer for two years with the Escondido Police Department, where he received an award for "best recruit" in the area of defense tactics, according to a 2015 newsletter from the department. According to the SDSO, Villanueva has now worked for the Vista substation for one year.

This lawsuit is the first of two. The attorney representing the Weick family, Angel Carrazco, is also representing the family of Jonathan Coronel, a suspect shot and killed in Vista by Villanueva earlier this month.

Carrazco plans on filing the lawsuit against Villanueva on behalf of Coronel's family in August.

Coronel, 24, was shot on July 5 after deputies spotted him in a Buick near North Melrose Drive and Knoll Road. The SDSO said Coronel was a documented gang member wanted on a probation violation.

The pursuit went through a residential neighborhood and, at one point, neighbors said Coronel tried to hide behind a house. When a woman spotted him, she forced him to leave. He reportedly walked across the street calmly, witnesses said, before hopping a fence into another person's backyard.

The SDSO said there was a confrontation between the pursuing deputy and Coronel before the deputy fired several times, killing the suspect.

NBC 7 reached out to the San Diego County Counsel. It said it would not be releasing comment because it has not been served yet.

The lawsuit was filed in federal court on July 19.