Minnesota Gov. Tim Pawlenty (R) has filed a friend-of-the-court brief in support of a lawsuit challenging the new healthcare law.

Pawlenty, a possible 2012 presidential candidate, has been a longtime critic of healthcare reform. In August, he restricted his state's participation in the new law, signing an executive order that directed state agencies to decline all discretionary participation. 

And he's said that repealing healthcare reform would be his campaign platform if he ran for president.

“I think ObamaCare is one of the worst pieces of legislation passed in the modern history of the country,” Pawlenty said on CNN’s "State of the Union" this weekend.

Voters signaled their unhappiness with the law during the 2010 midterm election, which returned control of the House to Republicans.

Rhode Island Gov. Donald Carcieri (R) joined Pawlenty in the brief, which states that the two governors are trying to safeguard their citizens from "federal abuse of the spending power." They argue that the law places liabilities on states through a Medicaid expansion program, according to The Associated Press.

A total of 20 states have signed on to the lawsuit, which originated in Florida. In October, a federal judge ruled the lawsuit could proceed.