WASHINGTON (AP) — A federal judge has cleared the way for a legal challenge by Congressional Republicans to President Obama’s health care law to proceed.

U.S. District Court Judge Rosemary M. Collyer ruled Wednesday that the House can pursue its claim that the administration violated the Constitution when it spent public money that was not appropriated by Congress. At issue is the more than $175 billion the government is paying health insurance companies over a decade to reimburse them for offering lower health care co-payments for poor people.

The House argues that Congress never specifically approved spending that money, and denied the administration’s request for it. The Obama administration insists it is instead relying on previously allocated money that it is allowed to use.