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Amid calls for shrinking government, lawmakers across the country are vowing to cut regulations that crimp economic growth. President Barack Obama recently said it's time to root out laws that "are just plain dumb."

Tell that to the cat groomers, tattoo artists, tree trimmers and about a dozen other specialists across the country who are clamoring for more rules governing small businesses.

They're asking to become state-licensed professionals, which would mean anyone wanting to be, say, a music therapist or a locksmith, would have to pay fees, apply for a license and in some cases, take classes and pass exams. The hope is that regulation will boost the prestige of their professions, provide oversight and protect consumers from shoddy work.

But economists—and workers shut out of fields by educational requirements or difficult exams—say licensing mostly serves as a form of protectionism, allowing veterans of the trade to box out competitors who might undercut them on price or offer new services.