The union representing 900 part-time faculty at Madison Area Technical College, also known as Madison College, sued the school on Monday.

Members of the bargaining unit argue they do not fall under the definition of public-sector employees in Gov. Scott Walker's anti-collective bargaining bill, Act 10, and should retain their collective bargaining rights.

"Our position is that (technical colleges) are an employer, but they aren't municipal employers, and people who work for them aren't state employees," said Mike Kent, president of the part-time teachers union.

The college said it would contest the lawsuit, which was filed Monday in Dane County Circuit Court before Judge Maryann Sumi.

"Clearly the technical colleges are part of Act 10 and fall within its reach," said Jon Anderson, a lawyer who represents the college. "They're clearly not private employers, which is what the union is in essence asserting."

At issue is the union's new contract with the college. The old contract expired in late June, and the two sides are negotiating a new contract. Under terms of Act 10, the 2011 state law that narrowed collective bargaining to cost-of-living pay raises, the union would be severely limited in those negotiations.

But the union argues that technical colleges, and their employees, fall outside the definition of "municipal employer" referred to in Act 10. If the court agrees, Kent said the union would retain collective bargaining rights.

The college has 20 days to answer the suit.