I am licensed to practice law in Mexico and NY. I was asked a similar question last year, and could not find anything that would make the alien inadmissible to Mexico. I even asked a person from the Mexican Foreign Service and was told that the Mexican immigration authorities did not ask about criminal record of visitors. As far as I know, the form filed by visitors at points of entry do not ask about it either.
Having said that, I did not find either something that would specifically allow foreigners with criminal record to enter into Mexico.
So this is not a "go ahead," but a "more likely, nothing will happen." Talk to your spouse and make a decision.
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