The ICE agent decided to use his gun 10 seconds before the shooting, when the car was stationary and he was in a safe location, to the right of it, and well behind the front. We know this because his own cellphone video shows him switching his cellphone into his left hand from his right. After a brief verbal interaction with the departing partner of Renee Good, and seeing her about to get into the vehicle, he chose to walk in front of it (a violation of procedure), with his hand on his service weapon.

She doesn't 'drive into him.' He engineered the situation by deciding to ready his service weapon and then leaving a place of safety to step in front of a vehicle whose occupants were visibly preparing to depart. Perhaps he learned this tactic in Border Patrol, where he used to work:

https://www.thenation.com/article/archive/us-border-agents-i...

Again, the first shot could be ruled to be justified, but the second and third were indisputably after the officer was out of harms way.

There's also unanswered questions about jurisdiction and whether the officers were acting within the scope of their duties, which would also be a major factor in the justification for use of force.