Washington (AFP) – The US Supreme Court heard arguments on Tuesday in a case brought by border state Texas challenging the federal government's right to decide which undocumented migrants should be targeted for deportation.

Defending the Biden's administration's policy, Solicitor General Elizabeth Prelogar said the federal government has to prioritize its efforts because it does not have the resources to pursue the 11 million undocumented “noncitizens” in the country.

“This is not about reducing enforcement of the immigration laws, it's about prioritizing limited resources to say go after Person A instead of Person B,” Prelogar said.

After more than two hours of arguments, the nine justices on the conservative-majority court did not appear to fall clearly on one side or the other of the case, which also raises thorny questions of the legality of state challenges to federal policies.

“It means that states can challenge the federal government on any policy with which they disagree,” Prelogar said. “Federal courts should not be transformed into open forums for each and every policy dispute between the states and the national government.”

Texas filed suit after the Department of Homeland Security, in a September 2021 memo, instructed US Immigration and Customs Enforcement (ICE) to concentrate expulsion efforts on persons who “pose a threat to national security, public safety, and border security.”

“We do not have the resources to apprehend and seek the removal of every one of these noncitizens,” Homeland Security Secretary Alejandro Mayorkas said. “Therefore, we need to exercise our discretion and determine whom to prioritize for immigration enforcement action.”

Texas solicitor general Judd Stone said prioritizing expulsion of undocumented migrants to certain categories of persons would impose costs on the state, which shares a border with Mexico and is an entry point for hundreds of thousands of immigrants every year.

“Texas suffers injuries, regardless of what it does, whether it detains, releases or paroles individuals because we have not only law enforcement costs, but social services costs and very serious threats of recidivism,” Stone said.

‘Zenith of federal power'

Elena Kagan, one of the three liberal justices on the court, appeared skeptical about the costs argument and the potential danger of limiting federal authority.

“Immigration policy is supposed to be the zenith of federal power,” Kagan said. “And instead, we're creating a system where a combination of states and courts can bring immigration policy to a dead halt.

“We're going to be in a situation where every administration is confronted by suits by states that can, you know, bring a policy to a dead halt, to a dead stop, by just showing a dollars worth of costs,” Kagan said.

Conservative Justice Brett Kavanaugh asked the Texas solicitor general what would happen if the court rules in favor of Texas, whose Republican governor has been sending busloads of immigrants to Democratic-ruled states.

“If you prevail here, what will happen?” Kavanaugh said. “That's a concern because I'm not sure much will change because they don't have the resources to change.”

The Biden administration's move to target individuals considered a threat to national security or public safety for deportation represented a shift from the policy of the administration of former president Donald Trump, which called for the expulsion of “all removable aliens.”

The Biden policy was immediately challenged by several Republican-led states as being too narrow and was blocked by a court in Texas.

The Supreme Court is expected to issue its ruling by the end of June.