Kyle Kershaw, who represents Police Officer Howie Lake II, told ABC News that Police Chief Murphy Paul didn't cave to pressure by people demanding he be fired.
"I think the chief did show courage because some people were calling for both of them to be terminated," Kershaw said, referring to Lake and Police Officer Blane Salamoni, the other officer involved in the fatal encounter.
Sterling, a 37-year-old black man, was shot and killed on July 5, 2016, after authorities and law enforcement officials claim he resisted after being confronted by Salamoni and Lake outside a Baton Rouge Triple S Convenience Store.
Unlike Salamoni, who drew his pistol and shot Sterling six times, Lake only used a stun gun twice.
Lake was suspended and for three days and docked pay for his role in the incident.
Paul concluded that both officers made bad decisions that led to Sterling's death.
"These actions were not minor deviations from policy, as they contributed to the outcome that resulted in the death of another human being," Paul said.
Kershaw, however, still railed the decision to punish Lake at all.
"There was absolutely no reason for Lake to be reprimanded for the force he used," Kershaw said. "Every step he took was non-lethal and by the book, and he met resistance every step of the way."
Kershaw told ABC News that his client was being disciplined specifically for "language he used" that night. He acknowledged that Lake, who was heard on the body camera and surveillance footage from the shooting released on Friday, used some profanities when he and Salamoni were squaring off with Sterling.
In the footage, Salamoni and Lake are heard using profanities to get the 327-pound Sterling under control.
At one point, Lake is heard barking orders at Sterling and using strong language. But Kershaw said that the four-year veteran was under a lot of duress.
"It happened when they were struggling and when they were on the ground," Kershaw said. "He was trying to make it clear: 'Hey don't do that!' It was completely reasonable.
Kershaw said he was going to meet with Lake to discuss in the coming week how to move forward. But for now, the news that Lake would be able to keep his badge was a major relief.
"I was being told they were both getting terminated," Kershaw said. "We were happy and surprised that didn't occur."
Meanwhile, Salamoni was fired by Chief Paul for shooting Sterling; his attorney, John McLindon, vowed to appeal that decision next week.
Despite criticizing the Salamoni's dismissal, McLindon praised for Paul supporting police officers in general.
"Although I disagree with his decision, what impressed me was he spoke to the community and said do not resist police officers, and give police officers the respect they deserve," McLindon said. "That hit home with us because if Alton Sterling had just complied, none of this would have happened.”
On Friday, Paul asked the public to respect police orders to prevents encounters from escalating.
"Treat our police officers with the respect that their positions deserve, and I assure you that the men and women of the Baton Rouge Police Department will reciprocate that gesture," Paul said. "Please stop resisting. Stop running. When a police officer gives you directions, listen."
A wrongful death lawsuit was filed last June by lawyers for Sterling's five children against both officers, the police department, its chief, and the city of Baton Rouge. The suit accuses the Baton Rouge Police Department of lax training and poor procedures -- factors that caused Sterling to be shot and killed.
The suit is still pending.
ABC News' Kate Hodgson contributed to this report.