Yes, as Vern said, make sure no one has a DUI on their record, even if it's old. They will likely be prohibited from entry since it's considered a felony in Canada.
Don't want to derail the thread, but this is not true. It is a very, very, very complicated subject with a good bit of nuance, and each indidivual person's situation will be unique.
Depends on how long ago it was.
Depends on if there was damage to person or property.
Depends on if there is anything else on their record, and if so, what that exact conviction was, when, how, etc.
Depends on what documentation the person has proving the above, that they satisfied all punishments/fines and when.
Depends on if you have done any legwork ahead of time trying to obtain a Temporary Resident Permit or Criminal Rehabilitation, or if you just show up ignorant or hoping to skate through.
Depends on your attitude when being questioned.
If anyone out there has a DUI on their record and wishes to enter Canada, I recommend you reach out to Kara:
https://beyondbordersimmigration.ca/about-us
