Roger Yu

USA TODAY

For decades, U.S. immigration policy has given priority to legal residents' family members.

Now, President Trump is signaling what could be a fundamental change in how the U.S. selects who gets to legally enter the U.S. – putting skilled or educated applicants first in line.

“Switching away from this current system of lower-skilled immigration, and instead adopting a merit-based system, will have many benefits: it will save countless dollars, raise workers' wages, and help struggling families --- including immigrant families --- enter the middle class,” Trump said in his speech to Congress Tuesday night.

Details are scant. But his tilt toward a merit-based policy could be a sound approach if it's executed properly and doesn’t come at the expense of other types of immigration, experts say. However, adopting a broader merit-based system while cutting other immigration visas could shrink the labor market and the tax base, and erode competitiveness in certain sectors -- such as hospitality, health care and food services – that rely on low-skilled workers, immigration.

“If what he’s talking about is expanding opportunities for skilled immigration and removing some barriers that exist to skilled immigration, that’d be a benefit to the U.S. economy,” says Howard Chang, immigration law professor at the University of Pennsylvania. "A concern I have is if the notion is to reduce immigration opportunities for those less skilled. That'd be unfortunate. Immigration of all skills contributes to the economy."

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The U.S. currently has employment-based immigration visas, based on skill level and education. But applicants and their job sponsors have to prove they’re filling vacancies that other Americans can’t fill or employers have difficulty filling. There’s an annual cap of about 140,000. “There are quality control requirements that make those visas difficult to get,” Chang says.

The U.S. also issues non-immigration visas for skilled workers.

Trump’s new policy could involve liberalizing or eliminating the overall cap or per-country quotas of the employment visa, as well as expanding job-type categories.

Trump could also borrow Canada’s playbook by enacting a “point-based” system. Immigration applicants to Canada are given points based on selection factors, including age, education, work experience and “adaptability.” Australia also has a point-based system that accounts for age, English language ability, skilled employment and education.

A U.S. Senate bill in 2013, now quashed, proposed a point system. “A lot of high-skilled sector workers are in high demand,” says Charles Hirschman, demographics and immigration professor at the University of Washington. “They’re much more likely to have patent breakthroughs and much more likely to start businesses.”

“There’s no sign that there are negative economic consequences (to immigration),” Hirschman adds.

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That is not what Trump asserted Wednesday in justifying his new proposal. “According to the National Academy of Sciences, our current immigration system costs America's taxpayers many billions of dollars a year,” Trump said, citing an influential immigration report released last year.

The National Academies of Sciences, Engineering, and Medicine, which issued the report, clarified Trump’s reference. Its report “concludes that immigration has an overall positive impact on long-run economic growth in the U.S.,” it said in a statement Wednesday.

“The long-term impact of immigration on the wages and employment of native-born workers overall is very small,” it said. “First-generation immigrants are more costly to governments than are the native-born, but the second generation are among the strongest fiscal and economic contributors in the U.S.”

Follow USA TODAY business reporter Roger Yu on Twitter @ByRogerYu.