First, get your computer back into your hands.
Then decide if it is worth the time and effort to pursue it criminally.
Last decide if you can find a better job with more trustworthy coworkers and bosses.
Every legal matter is fact specific, and there are often nuances in every case. This is intended for comment only, and does not create an attorney client relationship.
If you can get your computer back, then take it and move on with life. If you don't get it back right away, then go to small claims court and sue them all. And go to the commisioner and swear out criminal complaints against all of them. Let the court sort it out later.
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