He wants to fly through Canada one of these days to get to AK with an airplane. He heard that he could be turned away at the border by Canadian Customs and Immigration because of this. He did some research on it and read that it is the discression of the border security whether or not they let you in.
Another rumor is that it can be cleared up right away (within a month or two) by contacting a Canadian attorney that handles cases like this (A Pardon? Read below).
Has anyone had experience with this? Or at least know someone who has?
This is from the CANPASS page of the CBSA site:
http://www.cbsa-asfc.gc.ca/prog/canpass/faq_air-eng.html
6. If I have had a criminal conviction, can I join the CANPASS - Private Aircraft program?
If you have been convicted of a criminal offence, you might not qualify for the program unless you have obtained a pardon.
For U.S. citizens and permanent residents: alcohol-related driving offences, such as driving while intoxicated, driving while ability-impaired, and driving under the influence of alcohol, are criminal offences in Canada. You may want to contact a Canadian embassy or consulate in the United States to discuss immigration admissibility and legislative requirements.

