New York Mayor Michael Bloomberg released videos at 2 p.m. Wednesday that show violations of gun laws in three other states in a sting operation he authorized that cost city taxpayers $1.5 million and comes weeks before his bid for re-election.

The videos show seven gunshows in Ohio, Tennessee and Nevada where some vendors are featured "openly selling weapons to buyers who admitted they couldn't pass background checks," according to the Associated Press.

Supporters of gun control have fought against the "gun show loophole," in which unlicensed dealers can sell guns at trade shows, without performing background checks. New York is one of nine states, the AP reports, that require background checks on firearms sold at guns shows as well.

Nonetheless, federal law prohibits even unlicensed dealers from selling to people they suspect would fail a background check. Bloomberg says his videos show 19 out of 30 of these casual sellers broke that law, by selling to people who suggested they couldn't pass a background check.

The undercover investigators wore tiny cameras concealed in things like hats and purses and audio recorders in wristwatches, according to the Associated Press. Unlike the case of the undercover videographers who posed as a pimp and prostitute in ACORN offices and may have run afoul of Maryland's laws that forbid recording conversations without the consent of all participants, the operation does not appear to violate the laws of any of the states involved. Ohio and Tennessee allow one party to a conversation to tape another individual without their consent and the Nevada Attorney General's office said the sting does not violate their state's wiretap policies.

"Whether they see a camera or not, if they're in a public place it's legal," Edie Cartwright, spokeswoman for the Nevada Attorney General told Raw Story. "Particularly something like a trade show where people are walking around, etc. I think they expect there may be cameras or filming. It's a public place, it's kind of expected."

The New York Times notes that Bloomberg launched a similar sting operation in 2006 when investigators posing as gun buyers busted 15 dealers in five states making illegal sales, adding that the Justice Department under former President George W. Bush "warned" the Bloomberg administration about "the legality of its sting operation."

Bloomberg, who is the nominee of both the Republican and Independent Parties, hyped the sting on the liberal blog Huffington Post Wednesday, hours before the videos were publicly available.  Bloomberg said on the site that he authorized the investigation because the Bureau of Alcohol, Tobacco and Firearms reports that "89% of guns used in crimes in New York City last year originated out of state."

"Now, why is the Mayor of New York City investigating gun shows in places like Ohio, Tennessee, and Nevada? Good question. And the answer is: because I have no other choice," Bloomberg wrote. "Even though New York is the safest big city in the country, and safer than most mid-sized cities, and even though we have the nation's toughest law against illegal possession of a loaded handgun, drug dealers and criminals continue to obtain guns from inter-state traffickers."

Bloomberg is running for re-election on Nov. 3 against Democratic city comptroller Bill Thompson, but Thompson's campaign office did not immediately respond to Raw Story's requests for comment about the timing of the videos or the cost to taxpayers.

Many liberal blogs showcased Bloomberg's sting operation videos Wednesday, but the mayor still maintains ties to the GOP: Per the New York Daily News, Bloomberg will appear this month as a "special guest"  at a Bronx GOP annual autumn fundraiser with former Republican mayor Rudy Giuliani.

One of Bloomberg's videos appears below.

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