My sister has been charged with some rather serious white-collar crimes, including a couple that are felony level. She came out to me and told me about her activities a few months ago. Now I'm being asked to testify against her and turn over any information I have. I'm obviously not happy with her but she doesn't deserve to be locked up in the same place they send drug addicts and rapists. Today I wiped and physically destroyed the hard drives from her and my computers to secure them, my question is about testimony. I'm thinking of not even going, but if I do what should I say to keep her out of jail? Just give good character statements?

Edit: you all can stop telling I "can't" be untruthful about what I say. I don't care if it's technically illegal or not, I care about the end benefit. No one on planet earth is nearly important to me as my sister. I'm not a fan of what she's done but I'll do literally anything to defend her. I'll toss a fertilizer bomb into the prosecutor's bedroom if that's what it takes. Or you can help me settle it less dramatically.