Reminds me of the director of the royal coin cabinet in Stockholm, Sweden. He sold coins and medals from the museum for a value of 20 million sek (~$2m) through a coin collector/trader from 1997 until a few years ago. He could only be sentenced for selling 10% of those coin because of lack of evidence.

https://coinsweekly.com/theft-at-the-stockholm-royal-coin-ca...