He's probably going to get something along the lines of a 5 to 6 year incarceration and he'll be released afterwards with no charges. He'll probably have tons of hidden BTC somewhere and will remain a millionaire for the rest of his life. Would you be 5 years in jail to be released as a millionaire? maybe for some is a good deal.
Is Karples still a French citizen, and can he be deported from Japan after serving his time there? I know he married while in Japan, but I don't know if he married a Japanese citizen. Reuters says his wife now lives in Canada and I know that to get US citizenship you have to be married and cohabiting for about 7 years. Maybe the US will extradite him after he's served his Japanese time, then he can do some time in a US jail.
http://www.reuters.com/article/2014/04/21/us-bitcoin-mtgox-karpeles-mother-idUSBREA3K01J20140421Anne visited Karpeles in Japan, her first trip there, for 10 days from late-November last year, meeting his Japanese wife and their 2-year-old son Pierre.
"(The wife) has gone to Canada to live ... that didn't really help Mark, with all that's happening," Anne said, though she said she has more contact today with the wife than she does with her son.