CHICAGO (CN) – A Chicago cop shot an 86-year-old man in the back seven times, killing him in his own back yard, then shot his 91-year-old wife three times and conspired with other cops to maliciously prosecute her, the couple's children claim in court.

Hazel Jones, 91, says she was in her back yard on the South Side of Chicago on April 25 when defendant Chicago police Officer Courtney Hill entered the back yard with his wife.

Jones's husband, Joseph Huff, joined them, whereupon "without justification or provocation," Hill shot her husband eight times – seven times in the back, according to the complaint.

"Defendant Hill then shot Hazel Jones three times."

Their children, Joseph and Lisa Huff, sued Chicago and Hill on Tuesday, in Federal Court.

They claim, inter alia, that "City of Chicago police officers routinely, unlawfully conspire, cover-up and otherwise maintain a code of silence or 'blue wall' to protect their fellow officers who are engaged in misconduct while on duty. Defendant Hill shot and killed decedent Joseph Huff because he was aware of this practice and knew he would be protected by his fellow officers.

"As it pertains to the incident set forth herein, City of Chicago police officers specifically failed to (1) canvass the neighborhood and obtain statements from witnesses, (2) take proper crime-scene photographs, (3) properly collect evidence, and (4) preserve the crime-scene, in part, by allowing Officer Hill in to tamper with, contaminate and/or destroy evidence on scene.

"City of Chicago police officers also affirmatively acted to covered-up defendant Hill's unlawful conduct. In furtherance of this cover-up, defendant Hill engaged and conspired with other Chicago police officers to maliciously prosecute Hazel Jones for crimes she did not commit.

"Specifically, defendant Hill signed a criminal complaint against Hazel Jones for committing aggravated assault to a peace officer and battery."

The family seeks punitive damages for civil rights violations, excessive force, unlawful seizure, wrongful death, willful and wanton conduct, negligence, assault, battery, trespass, and intentional infliction of emotional distress.

They are represented by Abby Bakos, with Shiller Preyar Law Offices.

Residents of the neighborhood told the Chicago Tribune after the shooting that the two families, who were neighbors, had been feuding for a long time.