Right-wingers have been having fun in recent weeks with the ACORN "gotcha" videos supposedly showing community organizers indulging in illicit behavior. But they're about to discover that the undercover video can be a two-edged sword.

Over the past year, New York Mayor Michael Bloomberg has been sending out private investigators to gun shows around the country, focusing on locales where NYPD and other local law enforcement are seeing guns arriving from. And what they showed was incredibly revealing.

It shows the dirty little secret that everyone who attends gun shows with any kind of discerning eye can tell you: There are a lot of illegitimate transactions taking place at them -- and particularly a lot of sales of guns to people who could never pass a background check.

John Rosenthal described in some detail last year just how big the "gun show loophole" is. Like, Mack-truck sized:

At approximately 5,000 gun shows each year in 32 states, criminals and terrorists are allowed to purchase firearms from private gun dealers without an ID or background check. Although many gun dealers are federally licensed and therefore legally required to contact the National Instant Criminal Background Check System to ensure that a prospective purchaser is not prohibited from possessing firearms, private sellers have no such requirement.

The report produced by the New York mayor's office investigation -- which, along with the videos, will be available for public view at 11 a.m. PDT today (we'll post them at C&L then) -- reveals that 63 percent of the gun vendors approached by the team were willing to sell to a person who told them they couldn't pass the background check.

Unlike the phony ACORN undercover operation -- which only offered for public view a single instance of actual miscreancy, and refused to report the several instances in which they were turned away -- this report is clear that some gun vendors adhered to the law.

But some 19 out of the 30 vendors approached sold to investigators who said they'd probably fail a check. Along the way, they bought semi-automatic handguns and assault rifles. All told, 39 of 51 attempts to buy a gun illegally were successful. Several vendors told their buyers that they probably wouldn't pass a check either.

Only 11 vendors said no.

There were exchanges like this caught on tape:

"I don't need your address."

"No background check?"

"Nothing. Just show me that you're from Ohio."

"That's good about the background check because I probably couldn’t pass one."

"I don't care. All's I got to do is demand you show me your license."

"You don’t care about the background check, right?"

"Nope. Nope. I wouldn't pass either, bud." [grin]

"Is that right?"

This is why some 30 percent of all illegal gun traffic in the United States emanates from gun shows. It's long past time to shut this travesty down.

We'll be back later this morning with video and more details.