The Trump administration again asked the Supreme Court to step into the legal fight over the Deferred Action for Childhood Arrivals program on Monday, urging the justices to decide this term whether the government has the power to end the Obama-era immigration policy.

In three petitions from three appeals courts, the Department of Homeland Security and other Trump officials want a speedy high court review of whether the administration’s September 2017 decision to revoke the discretionary program was lawful, and whether the federal courts can review that decision at all.

The court action comes on the eve of a midterm election where President Donald Trump has made immigration enforcement a major issue as Republicans defend majorities in both the House and Senate.

The Justice Department filed the requests in ongoing legal challenges where lower court judges have concluded that ending DACA was either unlawful or likely was unlawful, but appeals courts have not yet reviewed the cases.

Federal courts have required the government to maintain the DACA policy nationwide that applies to more than 500,000 so-called “Dreamers” who arrived in the United States illegally as children, until the legal challenges are resolved.

The administration sought to wind down the program in March.

The Supreme Court would not be able to review the DACA issue until late 2019 at the earliest if the government waits for the regular appeals court process to play out, a Trump administration petition states.

“And the very existence of this litigation (and resulting uncertainty) would continue to impede efforts to enact legislation addressing the legitimate policy concerns underlying the DACA policy,” the Justice Department argues.

The legal fight is playing out on the heels of a fruitless attempt by the Senate to legislate a path to citizenship for Dreamers. There is a slim chance of senators taking up immigration again after three attempts to compromise — two of them bipartisan efforts — were rejected this year on procedural votes.

“No one contends that the policy is required by federal law,” the petition states. “Yet as a result of nationwide preliminary injunctions issued by the District Courts in the Northern District of California and the Eastern District of New York, DHS has been required to keep the policy in place, now more than a year since the agency’s decision.”

The justices in February declined a similar administration request to leapfrog an appeals court to have the high court step into the issue. But the Supreme Court also wrote in a two-line order: “It is assumed that the Court of Appeals will proceed expeditiously to decide this case.”

Watch: Why Are the Dreamers Called the Dreamers?