I'm Lucy, and I'd be happy to answer your questions today. I'm sorry to hear about your situation.
There's a cause of action for intentional infliction of emotional distress, which means behaving in an "extreme and outrageous manner," of a sort that is "intolerable in a civilized society," that serves no legitimate purpose and that is done solely to inflict emotional distress on someone else. There is NO LEGITIMATE REASON for sending death threats. Evidence that you've been damaged by this person's behavior could involve testimony about anxiety, insomnia, depression - whatever you're feeling. If you've spoken with a mental heath professional, you'll be able to seek reimbursement for your medical bills and out-of-pocket expenses in addition to punitive damages. The judge can impose whatever amount of money he or she thinks is appropriate to stop this person from engaging in death threats in the future, and that money goes to you.
Because he is targeting you in California, you can sue in California even if he lives in another state.
Also, what you're talking about is stalking. If this person is in California, contact your local police. You may also be able to get a no-contact order against him. If you're not sure where he is, or he's in another state, contact the Internet Crime Complaint Center and ask them to investigate. You can also block that person from seeing your public profiles, and report him to Twitter and other sites to see if you can get his IP address banned.
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