The rule means many green card and visa applicants could be turned down if they have low incomes or little education, and have used benefits such as most forms of Medicaid, food stamps, and housing vouchers, because they'd be deemed more likely to need government assistance in the future.
It will encourage "self-reliance and self-sufficiency for those seeking to come to or stay in the United States," said acting US Citizenship and Immigration Services Director Ken Cuccinelli, appearing in the White House briefing room. In doing so, though, it'll likely make it harder for low-income immigrants to come to the US.
When asked about whether the rule is unfairly targeting low-income immigrants, Cuccinelli said: "We certainly expect people of any income to be able to stand on their own two feet, so if people are not able to be self-sufficient, than this negative factor is going to bear very heavily against them in a decision about whether they'll be able to become a legal permanent resident. "
New York Attorney General Letitia James announced Monday evening that she plans to sue to block the rule.
"President Trump's new public charge rule is yet one more example of his Administration turning its back on people fighting to make a better life for them and their families," James said in a statement. "Under this rule, children will go hungry; families will go without medical care. I am committed to defending all of New York's communities, which is why I intend to sue the Trump Administration over this egregious rule."
Under current regulations put in place in 1996, the term "public charge" is defined as someone who is "primarily dependent" on government assistance, meaning it supplies more than half their income. But it only counted cash benefits, such as Temporary Assistance for Needy Families or Supplemental Security Income from Social Security.
Officials can take into account an applicant's financial resources, health, education, skills, family status and age. But few people are rejected on these relatively narrow grounds, experts said.
Immigrant advocates have argued that the rule goes beyond what Congress intended and would discriminate against those from poorer countries, keep families apart and prompt legal residents to forgo needed public aid, which could also impact their US citizen children.
They also said it would penalize even hard-working immigrants who only need a small bit of temporary assistance from the government.
"The rule reflects a dark vision of the United States -- as an unwelcoming nation that wants to keep out people who seek to join their family, work hard, and climb the economic ladder -- based on the erroneous assumption that they won't contribute to our communities, our economy, and our nation," said Robert Greenstein, president of the Center on Budget and Policy Priorities.
Democratic presidential candidate Beto O'Rourke immediately slammed the proposal
This regulation will have the "deepest, widest and most long term impact" of all of the immigration policies implemented by the Trump administration, said Marielena Hincapi, executive director of the National Immigration Law Center on Monday, adding that her organization and others are preparing to bring a lawsuit over the regulation.
There are exceptions to the rule, such as benefits received by active duty member of the military, Medicaid for pregnant women, children under 21 years old, and emergency medical care.
The rule also doesn't impact refugees or asylum seekers.
Earlier this year, President Donald Trump also issued a memorandum doubling down on a current law that requires immigrants' sponsors to take financial responsibility for certain income-based government benefits the immigrant receives. It's unclear whether enforcing the law would make any substantial difference.
Undocumented immigrants would not be affected -- unless an avenue opens up for them to apply for green cards or visas since they are largely ineligible for public aid.
Monday's regulation is likely to meet legal challenges, but it could still cause some who fear retribution to alter their daily lives.
Among low-income immigrant families, the figure was more than one in five, according to the study, which was based on a December 2018 survey of nearly 2,000 non-elderly adults who are foreign born or live with at least one foreign-born family member.
The rule includes immigrants who use one or more designated public benefits for 12 months within a 36-month period. Each benefit is counted separately, meaning if two benefits are used in a month, it'll count as two months. The rule will take effect October 15.
This story has been updated.