Senator Jeff Sessions (R., Ala.) and the Congressional Research Service compiled a list of “17 separate restrictions on agencies’ use of fees in the consolidated appropriations bill for FY 2014” into a memo on the eve of a crucial meeting of House Republicans debating how to respond to President Obama’s administrative amnesty.

The restrictions were passed and signed into law as part of the omnibus spending bill last year with the cooperation of President Obama and Senate Democrats, a point that buttresses the immigration hawks’ argument that Congress can block funding for the implementation of Obama’s latest executive orders.

This memo marks the second time in a week that Sessions has turned to the Congressional Research Service for help in making the case that Congress should use the power of the purse to fight Obama.

“In either case, the funds available to the agency through fee collections would be subject to the same potential restrictions imposed by Congress on the use of its appropriations as any other type of appropriated funds,” the CRS announced last week, per Breitbart.

House Republican appropriators have argued that Congress can’t practically withhold finding for the U.S Citizenship and Immigration Service’s efforts to implement the orders because the initiative runs on fees. The Department of Homeland Security, notably, emphasized last year that — even in a government shutdown — “fee for service activities such as those performed by U.S. Citizenship and Immigration Services” may continue.

To counteract that, Sessions has marshaled a list of congressional actions, topped by a restriction that lawmakers passed last year on how money for USCIS might be used for the purpose of providing an immigrant integration grants program.

“Notwithstanding section 1356(n) of title 8, United States Code, of the funds deposited into the Immigration Examinations Fee Account, $7,500,000 may be allocated by United States Citizenship and Immigration Services in fiscal year 2014 for the purpose of providing an immigrant integration grants program,” the first example on the memo reads.

House Republicans are meeting Tuesday morning to discuss their next move. The most aggressive of Obama’s opponents want the House to attempt to block the implementation of the immigration orders during the lame-duck session, even with Harry Reid still in control of the Senate. Alternatively, Republicans might decide to pass a short-term funding measure prevents the government from running out of money this month, yet leaves long-term policy decisions to the GOP-controlled Congress next year.

“The next 36 hours are going to be important,” House Republican Policy Committee chairman Luke Messer told Roll Call.