Think about it. DA's are elected into office. Once in, they care most about situations which will make it appear that they are tough on crime.
Which cases are those?
The ones that get publicity.
Get some publicity for your story and then contact the DA's office. Or, contact the DAs office, find out who is prosecuting the case and ask them what their plans are. They may plead it down...unless you tell them you will vocally and publicly disagree with them.
Lisa
PS of course it helps if you tell them you are a registered voter, boy.
Also, there is a difference between civil and criminal prosecution. In your original post, I inferred that you were writing about a civil case.
Whether a criminal case is prosecuted is up to the local DA. You can demand all you want and go to the press. Whether or not they find that situation compelling enough to write about it or show it on the news is another matter. Even then, the DA can choose to do nothing.
The DA is concerned about it being worth the time and money in relation to the crime committed. Also, they want to be assured that they can WIN. They don't want to spend any time on a case they think they will ultimately lose.
The guy who rear-ended the other is at fault! That doesn't stop him getting prosecuted for other 'technical' offences that are not to do with the issue of liability.
Haha! You can be unlucky....like carefully driving home having had one too many...only for someone to cause an accident! And you get done for drunk driving!