Explain your friends WHY you do that. They might even change their minds and be on your side.
Make it clear that you refuse to ease the burden of responsibility from her shoulders, and that she actually has to learn from the experience, in order to avoid even greater troubles in the future.
However, it would be nice of you to assist in "cleaning up the mess":
- help Rachel get the help she might need, convince her about it (nicely) if she is reluctant;
- help the injured person(s), if you are inclined to.
You are right that it is not helpful (long-term) to show the wrong kind of empathy to Rachel: make her believe that it was not her responsibility, and that it is OK to continue having a life of "crime".
I learned how to deal with it (unfortunately) in my family. My father was reckless and damaged some things around, had some minor injuries. My mother was angry at me for supporting him - she thought I told him that whatever he did was OK. I explained her the discussions I had with my father, and that even though I had a calm voice, I actually told him what he did wrong and how he can to better in the future - to avoid damaging stuff and to avoid harm, to himself and to others.
I even had a follow-up discussion with my father when my mother was present, so he understood hes "lesson" better, and my mother understood that I was not minimizing what happened.
Note: I found out (from my mistakes) that it is always advisable to show empathy. Not necessarily because the person deserves it, but because it is good training for yourself, to deal with future actions, when empathy is the key to fix things.
You need to understand that your situation has changed (I did not understand it myself, initially). In the past, you only needed to show empathy to Rachel. Now you have the new experience, to show "another" empathy to your friends, who do not understand WHY your attitude changed. You need to understand their point of view, and talk to them from there.
It will help greatly to keep any anger / revolt you have under very strict control. Even if you mention it, do not act on it. Control your voice, body movement, etc.
I understood this while (re)reading the article on Wikipedia about empathy.