I’m writing about someone who did something reckless, and that could have endangered others. Is she charged with reckless endangerment? Or is she charged with Reckless Endangerment?
Thanks.
Lower case; no capitals.
Not even capital crimes? 
Wouldn’t that depend on the sentence?
This is my vote (if we’re voting) and I propose that it is a context issue.
Whoosh! 
My take is that if you are referring to a specific, named offense that is defined in some legal code, then that takes capital letters. If you are referring to a general concept of a transgression against morality in general, then that takes all lowercase letters.
E.g.: “John committed theft. He was arrested and charged with Petty Theft Misdemeanor”.
The first sentence refers to theft in a general moral sense, disconnected from any specific legal codification of the concept. The second sentence refers to a specific statute under which a person can be formally charged under certain circumstances that would likely constitute a transgression against the moral concept of theft.
or
“Mary was caught trying to sell cocaine. She was charged with Possession of a Controlled Substance with Intent to Distribute in the First Degree.”
That was my thought as well, but I discussed it with my editor on Skype and he said lowercase, unless quoting an indictment. YMMV.