It is my understanding that Japan will allow you into the country for 90 days without the need for a Visa. You should not have a problem.
If you are truly concerned you can call the Japanese Embassy before you go. The Japanese Embassy is located at 299 Park Avenue, New York NY 10171, and their phone number is 212-371-8222.
I am not aware of any restrictions for travel to Japan due to a misdemeanor DWI conviction. You should be able to check the Japanese consulate online to find out for sure.
I concur with the other attorneys. 1 DUI conviction should not stop you from traveling to Japan.
Edward J. Blum
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