Democratic lawmaker Julia Brownley sent a political mailer to her constituents in late July featuring a woman wearing fake military attire and a German Luftwaffe insignia — apparently unaware that the costume was not an official uniform worn by U.S. personnel.

On Monday Jeff Gorell, Brownley’s Republican opponent in California’s 26 congressional district, sent out a press release highlighting the congresswoman’s taxpayer-funded faux pas.

The candidate claims that “concerned local veterans” brought to his attention a photograph featured along the top of the flyer — which also contains pictures of a young family, a child going to school, a vibrant classroom and other common campaign themes.

That photograph shows a young woman in a white, open-collared military uniform, wearing a white cap displaying a gold insignia and blue-and-gold trim.

Although it bears a fleeting resemblance to official attire worn by the U.S. Navy, no branch of the United States military wears a uniform like the one in the mailer. And the insignia on the cap is the symbol of the Bundeswehr Luftwaffe, Germany’s air force.

A look at all of the Bundeswehr’s official uniforms offers no similar outfit in any branch of the Germany military, lending credence to Gorell’s speculation that the picture is “a purchased stock photo of a model in a costume contrived from various emblems to look like an official [U.S.] naval uniform.”

“This gaff is disrespectful to those who have worn the uniform of the United States,” Gorell continues, calling it “indicative of a fundamental lack of understanding of veterans and the military by Brownley, her staff, and her political advisors.”

Brownley serves on the House Committee for Veteran Affairs and is ranking member on the House’s Subcommittee on Health, which oversees the VA. Her district includes Naval Base Ventura County, a large military installation near the southern California town of Oxnard that supports 19,000 naval personnel.

The congresswoman reportedly sent out the mailer under congressional “franking” privileges, which allow sitting lawmakers to mass mail certain types of flyers and other information to their constituents without paying postage. (RELATED: Democratic Congresswoman Elizabeth Esty Spends $183,700 On ‘Franking’)

It’s an advantage that incumbents frequently rely upon while campaigning, despite an official ban on overtly political messaging. Gorell demanded the congresswoman “apologize for using taxpayer funds to send out such wasteful, useless mailers.”

RealClearPolitics.com rates California 26 as battleground district that “leans Democratic.” But Gorell finished less than one point behind Brownley in the district’s open primary in June — the closest in any of California’s congressional races.

And last week Brownley used the specter of Obama’s impeachment by congressional Republicans as part of a fundraising email against Gorell — claiming he’s “going ALL-IN to shore up his radical Republican majority.” (RELATED: Boehner Rules Out Obama Impeachment: ‘A Scam Started By Democrats’)

But Gorell quickly informed a local journalist he was against impeaching the president, prompting the reporter to ask the Brownley campaign about the discrepancy. The congresswoman did not reply.

Brownley’s congressional office did not respond to a request for comment.

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