The conservative Republican's plans echo President Donald Trump's crackdown on immigration - an agenda Kobach has helped to shape. The president has endorsed Kobach , the Kansas secretary of state, who won a narrow primary victory over the state's GOP governor.
Plenty of immigration policy analysts suggest Kobach's push could harm the state's economy, but they start by questioning the dollar figure he is citing repeatedly as the annual cost of illegal immigration to Kansas. Kobach is undeterred.
"My election would send a signal that the public-benefits gravy train is going to end," Kobach said during a recent interview.
While states such as California and Illinois have offered immigrants sanctuary, Kobach wants Kansas to catch up to others including Missouri, Alabama and Arizona in setting policies designed to prevent immigrants living in the U.S. from getting jobs or obtaining benefits. Kobach has falsely described Kansas as the "sanctuary state of the Midwest."
His figure for what Kansas could save annually comes from a September 2017 report by the Federation for American Immigration Reform.
The group backs Trump's call to build a wall on the border with Mexico and opposes "amnesty," for immigrants living in the U.S. illegally, including a pathway to citizenship for those willing to serve in the military. Its website argues for cutting legal immigration 70 percent and says "immigration levels must fall" for U.S. wages to rise.
The group calculated figures for each state by tabulating a 50-state total for various costs and working from an estimate of how many immigrants living illegally in the U.S. reside in each state. FAIR estimated more than 84,000 immigrants live illegally in Kansas; other sources have lower figures. The total is between 2.2 percent and 2.9 percent of Kansas' population.
Almost half of the total costs the study cites are for public schooling for immigrant children. But a 1982 decision by the U.S. Supreme Court prohibits states from denying those children an education.
Roughly a third is a combination of policing, court expenses and even general services, such as garbage collection.
In short, much of the spending is for services a state can't avoid unless immigrants are deported or leave voluntarily.
Kobach acknowledged that he couldn't cut off much spending immediately and might not be able to completely eliminate his $377 million a year entirely over time but maintains reducing it sharply is worth doing. He's outlined multiple proposals for combatting illegal immigration.
FAIR research director Matt O'Brien, one of the report's authors, said the burden to federal and state governments from providing services "offsets any measurable gain" from money "illegal aliens are alleged to inject into the economy."
"In fact, illegal immigration simply amounts to a massive wealth redistribution scheme," O'Brien said in an email.
Critics contend the report that Kobach is citing overestimates how many immigrants live in the U.S. illegally and fails to adequately consider immigrant contributions to the economy. A senior policy analyst for the libertarian Cato Institute called it "fatally flawed" - and said it might overestimate net government costs by as much as 97 percent.
"It's disappointing that a candidate for such an important office is relying on such shoddy research to make his point," said Alex Nowrasteh, the Cato analyst. He argues for allowing "peaceful" immigrants to stay in the U.S. even if they arrived illegally.
The Democratic nominee for governor, state Sen. Laura Kelly, described the FAIR report as "widely discredited," adding in an email, "Kris Kobach is deceiving Kansans to further his personal political agenda."
And independent candidate Greg Orman, a Kansas City-area businessman, said: "We're not going to grow the Kansas economy by driving workers out of the state."
Federal law generally prohibits government health coverage and food assistance for illegal immigrants, though Kobach says Kansas is not aggressive enough in policing fraud in those programs.
But FAIR argues that costs for states are bigger and include general services that legal residents also receive, as well as the costs of prosecuting and incarcerating illegal-immigrant criminals and medical care that poor immigrant families can't afford but are entitled to by law.
In 2016, a study from the National Academies of Sciences, Engineering and Medicine concluded that first-generation immigrants are more costly in the short-term to states and local governments than native U.S. citizens, largely because of education costs. Kim Rueben, a senior fellow at the Urban Institute, which participated in the academies' study, said immigrant parents have more children on average.
But, she added, "Those kids are also going to be the future labor force."
Studies by the University of Missouri-Kansas City in 2013 and the University of Kansas in 2014 concluded that immigrants benefit the Kansas economy and pay for government services they use. Both also concluded that immigrants expand the Kansas economy.
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