Attorney Jonathan Arthur told CNN: "He was terrified that if he was going to move his hands below where Officer Gutierrez could have seen them to undo that seatbelt, they would have murdered him."
Apart from pointing their guns at him, the officers also pushed Lt Nazario to the ground and pepper sprayed him. The officers apparently believed the licence plate on his new SUV was missing.
Lt Nazario has filed a lawsuit for $1m in damages, arguing that the officers violated his first and fourth amendment rights. The lawsuit also claims that the officers used excessive force during the December traffic stop.
Mr Arthur said that his client was justified in feeling threatened enough to fear for his life. The attorney noted that the officers had their guns drawn as they approached the vehicle and issued conflicting orders towards Lt Nazario.
He said: "He displayed admirable calm, which is what I would expect from a United States army officer, to be able to remain that calm, knowing that one wrong move and you're going to die.
"It was made worse by the fact that we had one officer telling him to keep his hands out of the window while the other officer telling him that, you know, he needed to open the door and get out."
In body camera footage, one of the officers, Joe Gutierrez, can be heard telling the Black and Hispanic army officer that he's "fixin' to ride the lightning".
The lawsuit argues that this is a "colloquial expression for an execution," specifically referring to the electric chair.
Mr Arthur added: "You do everything right, you slow down, you submit to the authority of law enforcement, you do the right thing, you wait until a well-lit place to pull over, you're on a dark road, you don't want anybody to get hurt, and then the officers turn around and repay your courtesy with this."
Town Manager William Saunders told CNN on Sunday that Officer Gutierrez had been fired. The other officer, Daniel Crocker, has retained his employment.
Virginia Attorney General Mark Herring sent an information request to the police department in Windsor, Virginia on Monday saying that he was "deeply concerned" about the traffic stop.
He requested records going back as far as a decade, saying that he was investigating if there was an “unlawful pattern or practice of conduct” at the police department, The New York Times reported.
Mr Herring told CNN on Monday: "The officers' conduct we saw in the videos, it was appalling, it was dangerous, and it's unacceptable. And people of colour continue to experience brutality and being pepper-sprayed, even killed at the hands of law enforcement, and it's got to stop."
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