A few months before Democrats swept the 2006 elections, an outcry raged in the fringier corners of the immigration debate. Treasonous American officials were tipping off the Mexican government about the whereabouts of Minutemen patrols, the argument went, making it impossible for the private army bent on preventing undocumented immigrants from crossing the border to do their jobs.

The outcry made it to Congress, where Georgia Rep. Jack Kingston, a Republican, introduced an amendment clearly directed at the Minutemen story. The amendment barred the Department of Homeland Security from providing “a foreign government information relating to the activities of an organized volunteer civilian action group, operating in the State of California, Texas, New Mexico, or Arizona.”

Kingston’s amendment overwhelmingly passed the Republican-controlled Congress, including the votes of 76 Democrats, most of them from the party’s then-strong Blue Dog conservative wing. Another person voted for the measure, too: Rep. Bernie Sanders, an independent in the midst of the campaign that would send him the U.S. Senate.

The Minutemen have long since faded from the the national conversation and from memory — in an interview with BuzzFeed News, Kingston had to dig deep to remember the specifics of the vote, and other prominent Republican Minuteman supporters of the time didn’t recall it at all — but fears that the federal government is undermining efforts by local authorities to fight illegal immigration continue.

For Sanders, the amendment is another in a string of past votes that aren’t quite in line with the exact progressive priorities of 2015. Much like past positions on guns that the senator has had to navigate this year, his immigration positions have at times posed some challenges with the new Democratic base and the party’s priorities. He voted against the 2007 immigration bill backed by most Democrats on Capitol Hill and Latino groups (as well as the Bush administration then in the White House) but opposed by many in Sanders’s organized labor base. Sanders supported the comprehensive immigration bill that failed in Congress in 2013. Immigration is now a central part of his campaign — last month he released a detailed proposal includes most of what immigration advocates are seeking this cycle.

And just as with guns — Sanders advocated for things like assault weapons bans while also voting against some Democratic-backed legislation — he supported many of the key goals of immigration advocates in 2007 such as the pathway to citizenship. But in the end, Sanders voted against the overall immigration bill.

The 2006 vote is a bit different. The amendment was meant to protect the Minutemen, and only concerned the southern border of the United States. A short floor debate over the amendment took place on June 6, 2006. Republican backers of the amendment spoke of “the total lawlessness of people coming illegally over the border at night” and how the Minutmen — “definitely not politically correct in Washington, D.C.,” Kingston, the Republican sponsor said — “filled a void which the government was unable to fill.”

Rep. Olav Sabo, a Minnesota Democrat and ranking member on the Homeland Security Committee, was the sole member of his party to speak on the amendment.

“I claim the time in opposition; but, Mr. Chairman, I don't rise in opposition,” he said. He said Customs officials had told him they already didn’t share information with the Mexican government except for where required by treaty.

“If people want to put it in the bill, I guess that is okay because it apparently does nothing,” he quipped.

The Sanders campaign cited Sabo’s vote when explaining Sanders’ support for the largely symbolic, pro-Minuteman measure.

“People put forward nuisance amendments all the time,” Michael Briggs, Sanders’s top communications strategist and longtime aide, told BuzzFeed News. “In this case, the Customs and Border Patrol [according to Sabo] said it was a meaningless thing and [Sanders] and Sabo voted for it.”

Kingston did not recall the specifics of the the legislative wrangling that eventually passed the amendment with some Democratic support (it was not included in a final DHS funding bill passed by the Senate), but he recalled Sanders in Congress as an unpredictable iconoclast.

"One thing that is nice about a guy like that, he's really philosophically true. He's kind of like Ron Paul, you couldn't get him off his belief system,” Kingston said. “He was pretty true to what he believed in. He would kind of jump in and out of various issues — he wasn't just a dependable liberal yes vote any more than a Ron Paul would be a dependable conservative no vote.”

Historians of the Minuteman debate of the 2000s don’t remember the issues surrounding the amendment as a libertarian issue. Harel Shapira, a professor of sociology at the University of Texas at Austin and author of a 2013 book on the Minutemen, cast the debate as steeped in conspiracy theories and fears that the Bush administration was undermining those trying to protect the border.

“There was some set of documents published on the Mexican secretary of state website indicating that the U.S. Border Patrol would notify them when Minutemen were involved in apprehensions of immigrants. From my recollection, it was a fairly innocuous statement,” he told BuzzFeed News. “It became an ‘issue’ because it was interpreted by Minutemen and supporters as the U.S. government collaborating with an enemy state, and putting the lives of patriotic Americans at risk (i.e all of these patrols were framed as a military operation), so, as the Minutemen and their allies saw it, you don’t give away troop locations during battle, but this ostensibly is what was going on.”

Minutemen were actually quite public about where their patrols were headed, Shapira said, regularly posting them to the web. The outcry over the supposed conversations between DHS and the Mexican government was about something more, he said.

“It was a conflict over cooperation between U.S. and Mexico and ‘whose side’ the U.S. government was on. All at the symbolic level,” he recalled. “The Minutemen and their allies were very good about framing this is a war and the Minutemen were seen as soldiers, so giving info to the ‘enemy’ was understood as act of treason.”

Still, the amendment vote wasn’t a very important part of that debate. It got very little press coverage when it passed. The Southern Poverty Law Center condemned it in one piece, with top SPLC official Mark Potok saying it “sounds like another paranoid conspiracy theory of the Minutemen” in one California newspaper. Most other stories mentioned it near the bottom of stories about legislative wrangling between the Republican House and the Democratically-controlled Senate. Even the most fervent supporters of the Minutemen at the time didn’t find memories of it close to hand.

Tom Tancredo, the former Republican member of Congress from Colorado and author of the forward to a 2006 book supportive of the Minuteman cause, voted for Kingston’s amendment along with most Republicans. But he didn’t remember the specific vote.

“An amendment vote, it's not quite as noteworthy as a piece of legislation,” he said. Amendments are often plentiful in bills and come up fast, he said.

He did find it surprising that Sanders voted with him on the amendment, however.

"I certainly would never have expected it," he said.

