A rule change to the federal food stamp program proposed by the Trump administration would cause children in low-income families across the United States to go hungry, educators and hunger advocates told Congress on Thursday.

The four people who testified Thursday said that a proposed Agriculture Department rule change to the Supplemental Nutrition Assistance Program, or SNAP, was a fundamental misunderstanding of a regulation known as broad-based categorical eligibility, or BBCE. As of now, states are allowed to waive asset tests — ignoring whether recipients have a car, assets or savings — and raise gross income eligibility limits.

Currently, a family of three can qualify for SNAP if they earn 130 percent of the federal poverty level, or $27,700, or if states raise that to 200 percent, $40,840. The Agriculture Department proposes to do away with that state flexibility.

Critics argue that eliminating BBCE would limit states' flexibility to address their unique populations, leave more than 3 million people without access to food through SNAP and cause nearly a million children to lose their automatic enrollment in the national school breakfast and lunch programs.

The plan, the second of three proposed rule changes to SNAP by the Trump administration, is expected to take effect soon. An earlier rule will impose stricter work requirements on able-bodied adults without disabilities, and it is expected to cut benefits to approximately 700,000 people when it takes effect April 1.

Many families across the country have gross incomes slightly above 130 percent of poverty but still have difficulty feeding their families because of the other financial burdens like housing, child care and medical benefits, Lisa Davis, senior vice president of the No Kid Hungry Campaign, testified Thursday.

The point of SNAP is to provide those families with some savings so they can become financially secure and move out of poverty, while reducing bureaucratic red tape, she said.

"BBCE allows these families to remain eligible for SNAP and free school meals," Davis said. "It creates efficiency and reduces administrative burdens on state agencies and schools, but most importantly it encourages work. It helps low-income families move out of poverty and build financial security. It allows them to accumulate modest assets to weather an unexpected financial crisis. It also ensures that their children can receive the nutrition they need at home and at school."

About 96 percent of the children who would be slated to lose automatic enrollment under of the Trump administration's proposed rule would remain eligible for free or reduced school breakfasts or lunches, but they would have to fill out separate applications.

SNAP provided benefits to 40.4 million people during an average month of the 2018 fiscal year, according to the Agriculture Department, with the average benefit measuring about $126 per person per month. Despite that help, 47.5 percent of households that received the benefit were food insecure.

Rep. Raja Krishnamoorthi, D-Ill., chairman of the Oversight Subcommittee on Economic and Consumer Policy, said BBCE also helped incentivize work. Recipients don't feel as though they must turn down work to remain eligible for their SNAP benefits, and it also allows them to own a car to drive to work or save money for potential emergencies, he said.

Krishnamoorthi cited his own story as an example of how SNAP helped his family rise out of poverty after they immigrated to the United States from India.

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"When we needed help, we were able to receive food stamps as my parents worked their way out of that difficult time," Krishnamoorthi said in his opening statement. "Today, my father is an engineering professor, my brother is a doctor, and I am fortunate to represent Illinois' 8th Congressional District in Congress and to chair this subcommittee. That was my family's American dream, and it was possible because of my parents' hard work but also because of the opportunities our country presents."

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Thursday's hearing was one of four held by the Oversight Committee to examine whether the Trump administration's proposed regulations would harm children.

The Agriculture Department, however, maintained that its goals in changing SNAP eligibility is to thwart exploitation of the program, which Agriculture Secretary Sonny Perdue said states had allowed without limit.

"For too long, this loophole has been used to effectively bypass important eligibility guidelines. Too often, states have misused this flexibility without restraint," Perdue said in a statement. "The American people expect their government to be fair, efficient and to have integrity — just as they do in their own homes, businesses and communities. That is why we are changing the rules, preventing abuse of a critical safety net system."

Unintended consequences

Craig Gundersen, an agricultural and consumer economics professor at the University of Illinois at Urbana-Champaign who has studied the program for more than two decades, said the rule would only make food insecurity worse in the United States.

He estimated that a third of the 3 million people who receive benefits through BBCE are food insecure, while another third — or 1 million people — would become food insecure.

While the Agriculture Department said it aims to save taxpayer dollars, he said, the increase in food insecurity would also have unintended financial consequences, most notably a nearly $1,800 increase in health care costs per person, according to a study he worked on for the Centers for Disease Control and Prevention last year.

"Food insecurity has costs," Gundersen said. "When we cut back on SNAP benefits, what that means is health care costs will increase, because you'll have more food insecure households. A lot of these cuts are borne by the government through Medicaid, Medicare, through individuals, because individuals go to the hospitals for uncompensated care. People are still bearing these costs."

Gundersen said this was a nonpartisan issue affecting blue states and red states. He said that Florida's and Nevada's BBCE rules are set at 200 percent above the poverty line and that Texas' is set at 165 percent.

A combined 636,800 people stand to lose access to their SNAP benefits in those three states alone, according to an Urban Institute analysis that examined the effect the rule would have had if it was implemented in 2018.

State officials in Michigan expressed particular concern after they recently raised the state's asset limit to $15,000 and where more than 125,000 people are at risk of losing benefits with the rule change.

"It enables families that have worked, saved and hit a rough patch to get the help they need without having to spend every penny they have in the bank," said Robert Gordon, director of the Michigan Department of Health and Human Services.

"We talked about the challenges for someone who works as a waitress, works in a car factory that closed and they lost their job. Why would we say to them that they should spend their life savings before they get help for food?" Gordon asked. "What if the next day their roof caves in or they have a sick child?"

Furthermore, he said, eliminating the rule could be so stringent that it would impose a cliff effect that discourages work, which is antithetical to the Trump administration's stated goals in changing access to SNAP.

"If you say now to states that it's only 130 percent of the poverty line that are currently eligible, then some people are going to say, 'Look, if I don't cut back my income, I'm going to lose my SNAP benefits, so then it doesn't pay for me to work,'" Gundersen said.

Food banks are also concerned, as they are worried they will have to make up for the 1 billion meals SNAP provided last year to families, according to an analysis by Feeding America, a hunger relief organization.

That would be an impossible task, according to Robert Campbell, managing director of policy at Feeding America.

For every meal provided by food banks, SNAP provided nine, he said.

"SNAP is the first line of defense for millions and millions of people around this country," Campbell said. "The change will only lead to families consciously making trade-offs between food and medicine, food and health care."

One of those testifying Thursday, Tega Toney, a high school teacher who is vice president of the American Federation of Teachers West Virginia, told NBC News before her appearance that access to SNAP removes a burden from students who already face difficult circumstances. Her students, she said, are not numbers on a spreadsheet but "real live kids with real issues."

"The deck is really stacked against them with the opioid epidemic, the poverty issues we're having, the declining economic revenue we're having," she said. "They're struggling as it is, so when we add this new layer to their everyday routine of 'How am I going to get food? How am I going to eat?' it just adds a harmful burden for these kids."