I'm Lucy, and I'd be happy to answer your questions today. I'm very sorry that this happened.
When someone knowingly files false charges against a person, that's called "malicious prosecution." Your brother in law should also know that it's a crime to file false charge against someone - you could file a police report. Damages for malicious prosecution include your legal fees in getting the matter dropped, false wages for any missed work, and reimbursement for the fines you paid. If you have paid a lawyer to get the charges expunged from your record (which you should be able to do), you can seek reimbursement of those fees as well. You can also include a claim for defamation of character, since he would have known that Amber Alerts go viral and it would smear your reputation. Both of these causes of action include punitive damages.
On top of that, he can be sued for attempted malicious prosecution for trying to talk your friend into reporting a borrowed car falsely as stolen. That can be included with the other counts.
And if you haven't done so already, you may want to talk to his superior officer about the way your brother-in-law abused his position as a police officer. Police officers are public servants, not gods. He's supposed to serve and protect society, not to exploit other people to benefit himself.
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