(CNN) — After killing a man at an Ohio Walmart, police interrogated his girlfriend, accusing her of lying, threatening her with jail time and suggesting she could be on drugs, according to a video posted on The Guardian’s website.

The man, John Crawford III, was holding an air rifle he had picked up off a store shelf when police shot him. A prosecutor called the case a “perfect storm” with “no bad guys,” but the family has said police used excessive force.

A grand jury decided not to indict the officer who pulled the trigger in the August 5 shooting at a Walmart store in Beavercreek, Ohio. While the Justice Department investigates the case, Crawford’s name — along with Michael Brown and Eric Garner — is being chanted by some demonstrators across the country protesting what they say is systemic racism that fuels police violence.

Now, the family’s lawyer says the recently released interrogation video shows police were trying to force Crawford’s girlfriend to say something to justify what they’d done.

 

“This was just an effort to cover up this bad shooting,” attorney Michael Wright said.

Wright on Tuesday said his legal team filed a federal civil lawsuit against two police officers; Beavercreek’s police chief; the city of Beavercreek and its police department; and Walmart.

The Crawford family is seeking at least $75,000 in compensatory damages and an unstated amount for punitive damages, the suit said.

The family alleges, among other things, that the police officers did not do due diligence to determine that Wright wasn’t a threat; that the officers didn’t give him enough time to put down the weapon; and that Walmart was negligent because the air rifle had been resting on a shelf, unpackaged, for at least two days, the family’s lawyers said Tuesday.

“By filing this civil lawsuit, we want to bring change in the policies of the Beavercreek Police Department and the merchandising practices of the Walmart corporation,” Wright said. “We want to make sure that this tragedy does not happen to any other family.”

Family of man killed sues police, Walmart

Tense interrogation

In the interrogation video, which was posted on The Guardian’s website on Sunday, a police detective repeatedly presses Crawford’s tearful girlfriend, asking her where Crawford got the gun he had in the store.

“You understand that we’re investigating a serious incident,” Detective Rodney Curd says. “You lie to me and you might be on your way to jail.”

“I swear to God, on my job, my family, on everything I love,” Tasha Thomas replies, telling the detective repeatedly that she never saw Crawford with a weapon and that she’ll take a polygraph test to prove it.

As she cries, the detective appears unconvinced.

“Why would he have a gun in the store?” he asks.

“I don’t know,” she replies.

“Did he carry a gun?” the detective continues.

“Not that I….I’ve never known him to have a gun,” she says.

Her response appears to upset the detective.

“Don’t tell me, ‘not that you know,’ because that’s the first thing that I realize that somebody’s not telling me the truth, when they say that kind of stuff,” Curd says.

By the end of the six-minute excerpt of the 90-minute interrogation posted by The Guardian, Thomas sobs as she buries her head in her hands.

The detective says he’ll write down her testimony, but then asks whether she’s under the influence of drugs or alcohol.

“Your eyes are kind of messed up looking and you seem a little lethargic at times,” he says, “and I don’t know if it’s because you’re upset or not. I just want to make sure what’s going on.”

Detective: ‘I was very direct in my questions’

Police have not responded to several requests from CNN for comment on the video. In a statement officials released in September, Curd describes his questioning of Thomas at the police department.

“The initial information I had was that (Crawford) may have brought a gun into the store with him. So I was very direct in my questions that I was having problems believing she would have not seen him bring a gun into the store,” he wrote. “She became emotional during the interview and started crying, saying that she is not lying, she will take a lie detector test and do whatever she needs to do.”

In his report, Curd wrote that it was only later when he was at the Walmart that he learned where the gun came from.

“I also learned while on scene that the rifle involved was a pellet gun that was taken from a box while he was inside the store,” he wrote. “This would also agree with the statement that she made that he did not take any type of firearm out of her car into the store with him.”

Attorney: Interrogation shows police ‘tried to cover it up’

Wright said police knew Crawford didn’t have a firearm when he walked into the Walmart.

“He was not an imminent threat to anyone. He was just shopping,” he said.

After the grand jury decided in September not to indict the police officers who were involved in the shooting, prosecutor Mark Piepmeier said a “perfect storm of circumstances” led to Crawford’s death and noted that the air gun bore a strong resemblance to an actual automatic weapon.

“It is very hard to tell the difference,” Piepmeier said.

Police responded to the scene after a witness called 911 and told dispatchers that Crawford was walking around with a rifle and “waving it back and forth.”

According to police, when officers arrived, Crawford did not comply with their commands to drop his weapon. And the Crawford family’s lawyers say police didn’t give him enough time to put down the weapon.

But Wright said that because Crawford was black, police made assumptions.

“The officers ran into an aisle, saw a black man with what they perceived to be a gun, and shot him on sight,” he said.

The interrogation video, he said, shows how police handled the case from day one.

“They, in their mind, had it made up that Mr. Crawford was a criminal, and they proceeded based on that without doing anything to independently corroborate what was actually happening in the store,” he said. “And they tried to cover it up by interrogating Miss Thomas in such a manner to try to get her to make a statement that would justify them shooting and killing Mr. Crawford that evening.”