[cucumber3732842]

After adjusting for socioeconomic factors auto theft in the US is pretty much a straight gradient based on "how quickly can it be in mexico"

Arizona, New Mexico and Socal have pretty high auto theft rates as well.

[ProllyInfamous]

This would be my answer, having grown up in Texas just hours from the border.

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Now that I live 1,000+ miles-more, inland, I definitely keep more of these opinions to myself – but decades of Texceptionalism (indoctrination, the Tejas way) definitely affects one's opinion on proximity to Mexico.

[emodendroket]

So do Washington, DC and Colorado but those don't really seem to fit your theory.