An arrest warrant says 16-year-old Jose Cruz was "intentionally shot" by off-duty Farmers Branch police officer Ken Johnson.

For that, Johnson is charged with murder.

Further, the warrant says Johnson "intentionally shot" 16-year-old Edgar Rodriguez in the hand and head. Rodriguez survived, but remains in critical condition at a local hospital.

For that, Johnson is charged with aggravated assault.

Neither teen was armed.

"You can only use deadly force if you have reasonable belief that someone is about to use deadly force against you," said former prosecutor and local defense attorney Toby Shook. "You can't just shoot someone because they stole from you."

Johnson, 35, was arrested Wednesday in connection with the Sunday shooting that he says began when the teens broke into his SUV at his Farmers Branch apartment complex. Video shows Johnson chasing the Cruz's red Dodge Challenger down Marsh Lane, appearing to ram the back of it, causing it to spin and crash.

A picture taken by bystander allegedly shows Johnson pointing a gun at the car.

The warrant says Johnson used a semi-automatic handgun to shoot the teens. It says that he was "standing in the roadway" at Marsh Lane and Spring Valley Road with the gun when officers arrived.

Johnson has been released on bail. He has been placed on administrative leave, pending the outcome of an administrative investigation. He could not be reached for comment.

In many ways, Johnson's arrest is historic. It marks the time first time in decades that an officer has been arrested on a murder charge in Dallas. It's also different than other recent cases involving officers accused of crimes in shootings. Specifically, Johnson was off duty, in civilian clothing and chasing the teens in his private vehicle.

"Addison has taken the position that they had to look at like he was a civilian and not apply a different standard," Shook said.

Shook is currently on the defense team in two cases involving former Dallas officers accused of aggravated assault and a Garland officer accused of manslaughter. Those incidents occurred on-duty unlike this situation involving Johnson.

Chris Livingston, Johnson's attorney, has blasted Addison for the way they went about arresting Johnson.

He says Johnson was being interviewed by Farmers Branch internal investigators when Addison police notified Johnson that they were coming to arrest him on Wednesday.

"This goes against decades of precedence of presenting these cases to a grand jury and I wonder whether or not the reason this is being is because he's a black officer," Livingston said.

He said that the surveillance video in the case is consistent with Johnson's statement that he was in fear of his life when he took law enforcement action.

"They were in the middle of committing a crime and they did not follow orders," Livingston said. "They indicated and they gave a threat to Officer Johnson. "

Livingston declined to reveal the nature of that threat.

Shook said it's telling that Addison didn't wait for a grand jury ruling.

"It tells me that they have some significant piece of evidence -- either a video tape or eyewitness testimony that they feel is strong enough for them to move forward quickly," he said.

The Dallas County District Attorney’s Office issued a statement Thursday, saying that law enforcement agencies have the option when there is enough probable cause to obtain an arrest warrant.

"The grand jury will be given this case in its entirety and all parties will have the opportunity to address them," the statement said. "Only then, will the grand jury makes a decision as to whether Ken Johnson is charged."

In a statement issued Wednesday, Addison Police Chief Paul Spencer said the department had the “probable cause” to make the arrest.

“This is a rapidly-evolving situation and it remains an active investigation,” he said. “Therefore, we are refraining at this time from discussing the evidence collected thus far or about the specifics of this case.

“We expect there are still several weeks of additional investigative work to do.”

Shook also said the officer will likely make a claim of self-defense.

The key will be what happened at the moment he fired his weapon.

“The fact that he's had training as a law enforcement officer could work for him. It could work against him,” Shook said. “Should he have kept his head much cooler? Did he react too quickly? Was he just angry or did his training tell him that he only a few seconds to react?”

Other cases of officers charged in shootings:

  • Former Dallas police officer Cardan Spencer is charged with aggravated assault in the Oct. 2013 shooting of a mentally ill man who was standing still with a knife at his side. He was fired and indicted.
  • Former Dallas police officer Amy Wilburn is also charged with aggravated assault for the December 2013 shooting an unarmed robbery suspect who an independent witness said had his hand up. Wilburn shot him at the end of a chase. She has said she believed he was reaching for a weapon. She was fired and indicted.
  • Former Garland police officer Patrick Tuter is charged with manslaughter in an August 2012 incident in which he shot a fleeing suspect 41 times. He was fired and indicted.