CHICAGO (CBS) — The family of 25-year-old Rashad Cunningham has filed a federal lawsuit against the city of Gary, Indiana, and Police Officer Isaiah Price, accusing the officer of fatally shooting Cunningham without justification in August.

Civil rights attorney Andrew Stroth said Price approached Cunningham as he and two friends were sitting in a car outside his home in Gary on Aug. 17, shined a flashlight into the vehicle, and within 10 seconds shot Cunningham at close range.

“Rashad Cunningham was sitting in his own car, minding his own business, in front of his home with two friends,” Stroth said. “At that time of the shooting, Rashad was holding his driver’s license and his wallet, and did not present a threat to Officer Price or anyone else.”

Stroth’s family said he was a father of five who was working to move his family out of Gary.

“My son, Rashad Cunningham, was shot down in cold blood sitting in front of his home by Officer Isaiah Price III,” said Cunningham’s mother, Tonia Simmons. “I will never see my son again. He will never be able to see his kids. It is just so sad, it is very devastating.”

Stroth said, while there is no dashboard or body camera video of the shooting, two eyewitnesses have said Cunningham was not a threat to police.

Cunningham’s family said Gary police have yet to explain exactly why the officer opened fire. Police have only said officers were responding to a call of shots fired when they approached Cunningham’s vehicle, and that Cunningham had a gun in his lap.

“We want answers. We haven’t got anything. We want something,” his mother said. “We are going to get justice and we are going to get answers and we are not going to stop until we get exactly that for Rashad Cunningham. We’re going to get justice.”

However, Cunningham’s lawyers said he was holding only his license and wallet in his hands, and that he was licensed to carry a weapon. The lawsuit also claims neither Price nor his partner issues any warnings to Cunningham or the others in the car before the officer opened fire.

According to Stroth, Price has a history of excessive force and other misconduct.

“At every level, the city of Gary failed. The city, the mayor of the city, the chief of police, they all allowed an officer with a history of excessive force, and abuse, and lying, and falsifying records to continue working in our community,” he said. “In this case, thank God there’s evidence with those two witnesses, because I will tell you black men are being killed across the country, and if there’s no evidence or eyewitnesses you can’t prosecute criminally or civilly.”

Stroth and attorney Greg Kulis said Cunningham had a clear Second Amendment right to carry a gun at the time of the shooting, and had no criminal record.

“This was a strong black man raising his family,” Stroth said. “A mother lost her son. A father lost his son. Brothers and sisters lost their brother. Five young children no longer have their father, because of the unjustified actions of Officer Price.”

Stroth also criticized the Gary Police Department for failing to require officers to use body cameras or dashboard cameras which could have recorded video of the shooting.

In addition to the lawsuit seeking to hold Price and the city of Gary financially liable for Cunningham’s death, Stroth called for an independent investigation of the shooting to determine if Price should be indicted and convicted of a crime.

Cunningham’s girlfriend, Heather Fox, said Price also should be fired.

“Officer Isiah Price III is one of the bad police that has to go,” she said. “Under what measure did Officer Price think it was okay to open fire and shoot somebody five to six times while his hands were up?”

According to a spokesperson with the city of Gary, “the city does not have a comment pending litigation.”

Price is on administrative duty.