Pro-labor advocates are criticizing a new addition to the Senate’s omnibus spending bill, a provision they say would quadruple the number of H-2B visas for unskilled guest workers, for a total of more than 250,000. The visa program has been described by the AFL-CIO as “deeply harmful” to American workers; and the omnibus insert, sponsored by Senator Barbara Mikulski (D., Md.) and Senator Thom Tillis (R., N.C.), has already been condemned by a bipartisan group of senators, including Bernie Sanders (D., Vt.), Richard Blumenthal (D., Conn.), and Jeff Sessions (R., Al.).

The Mikulski-Tillis bill appears to be a copy of the Save Our Small and Seasonal Business Act (SOSSBA). Like SOSSBA, the Mikulski-Tillis bill would exclude returning H-2B temporary workers from the normal annual cap of 66,000. Although SOSSBA was previously in place, Congress failed to renew it in 2008.

The H-2B program is designed to import temporary, seasonal, non-agricultural guest workers, mostly in the areas of landscaping, forestry, hotels, seafood processing, restaurants, amusement parks, and construction. Many of these unskilled jobs traditionally go to society’s most vulnerable — including single women, the disabled, the elderly, minorities, teenagers, students, and first-generation immigrants. H-2B employers love the program because, as with the H-1B program for skilled foreigners, the worker’s visa is tied to his employment, which makes him less likely to unionize. Unsurprisingly, the Chamber of Commerce lists expanding the H-2B program as one of its “Policy Priorities for 2015.” And like most of our immigration programs, the H-2B operates mechanistically, giving jobs to foreign workers without any consideration for domestic labor conditions: Regardless of the state of the economy, the cap stays the same.

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Although SOSSBA includes a reference to “small businesses,” most H-2B employers, according to the Center for Immigration Studies (CIS), are not small or seasonal; in fact, they are mid- to large-size companies and recruiters who petition for H-2Bs so they can hire employees who work in the U.S. for ten months out of the year, year after year. The benefit to H-2B employers’ operating costs is apparently worth the lobbying effort. In 2008, CIS found that Senator Mikulski, a long-time champion of SOSSBA, received tens of thousands of dollars of campaign contributions from the biggest users of the program.

Like Maryland, Tillis’s state of North Carolina is a big user of the program. His state in particular was recently the subject of an investigative Buzzfeed report about H-2Bs. The report, which also profiled the nearly identical H-2A program for temporary agricultural workers, zeroed in on the program’s loopholes and its damaging effects on American labor, most notably on African Americans.

As the report details, although the program requires employers to advertise job openings prior to petitioning for guest workers (which is not a requirement in the skilled H-1B program), the ads are designed to attract as little attention from American workers as possible. Buzzfeed found that while employers do post ads for American workers, they employ numerous strategies to make sure no one actually responds. The investigation found that one guest-worker employer, Talbott’s Honey of South Dakota, ran ads in newspapers in Texas and New Mexico, hundreds of miles away from its area of operation. Similarly, in North Carolina, the state’s online job board incorrectly posted seasonal Christmas-tree-cutting jobs “in the wrong counties, sometimes hundreds of miles from any pine forests.” As a result, Buzzfeed wrote, “workers looking for Christmas tree work close to home face a peculiar paradox: The only way to find the openings nearby is to search in a faraway corner of the state.” Other ads across the country simply failed to include contact information or the name of the company.

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Another tactic of H-2B petitioners is to include overly stringent requirements in the want ads. Lori Johnson, a lawyer from Legal Aid of North Carolina, told Buzzfeed that there is little evidence such requirements are ever imposed on the foreign guest workers who ultimately get the jobs. The ads are designed to “filter out U.S. workers,” Johnson concludes. Other job requirements, according to Buzzfeed, were specifically designed to keep African Americans from applying.

Such tactics surely explain in part why, in the Fiscal Year that ended in July, only 505 American farmworkers in the Tar Heel state found jobs from listings on North Carolina’s Department of Commerce’s website, even though more than 7,000 American farmworkers in the state had registered with the agency to seek work.

Quadrupling the number of H-2B visas will artificially increase competition for the jobs that typically go to the nation’s most vulnerable. Black unemployment in North Carolina, for instance, is 17 percent, four times the U.S. average and the fourth-highest rate for blacks across the nation. Members of Congress from Maryland and North Carolina, such as Congressional Black Caucus chairman G. K. Butterfield (D., N.C.), should join the bipartisan effort to condemn the bill.

— Ian Smith is an attorney who works for the Immigration Reform Law Institute.