Wisconsin Governor Scott Walker wants to fortify his anti-union credentials with a court victory as he maneuvers for a likely run for the Republican presidential nomination next year.

The second-term governor this month enacted a law barring unions from collecting fees from workers who don’t join them.

To keep that legislative victory intact, Wisconsin Attorney General Brad Schimel must repel union claims that the law forces them to represent non-members free of charge, violating the U.S. Constitution. Three labor groups are asking a state judge in Madison on Thursday to block the measure known as Act 1.

Their demand comes as Walker begins wooing voters in Iowa and while newly elected Republican Governor Bruce Rauner in neighboring Illinois fights to preserve his own executive order barring non-union public workers from being forced to pay so- called fair-share fees.

When Walker signed the right-to-work bill on March 9, Wisconsin became the 25th state to enact such a law. Those states include Iowa, Indiana and Michigan. While a lawsuit over Michigan’s measure is still pending in a Detroit federal court, the Indiana provision withstood state and federal lawsuits.

Wisconsin is likely to win the court fight, said Marquette University professor Paul Secunda, director of that school’s Labor and Employment Law program in Milwaukee.

Technical Argument

While there’s a technical argument that not being able to collect union dues amounts to an unjustified taking of compensation, right-to-work laws have existed since the 1950s, said Secunda, adding he’s opposed to Act 1.

“None have ever been struck down on a constitutional challenge,” he said.

The case challenging Walker’s law was filed March 10, the day after the governor signed it. Its opponents include the Wisconsin State AFL-CIO which, according to its complaint, represents more than 200 affiliated groups with 100,000 private- sector workers among them.

State law requires unions to represent the majority of a workplace’s employees, according to the labor groups. State and federal laws require unions to represent everyone in a unionized workplace fairly whether they’re members or not.

Act 1 makes it a crime to require the payment of union fees by non-members as a condition of employment, the groups said in court papers.

Fair Share

It amounts to an unconstitutional taking of property, they contend, by “simultaneously compelling the unions to represent non-members while disabling the unions from collecting any fair share fees or charges of any kind or amount from them.”

The state’s attorney general contends “Act 1 does no such thing” Right-to-work laws are allowed by the federal National Labor Relations Act, Schimel, a Republican, said in court filings.

States are allowed to choose between fair-share union security agreements, or right-to-work provisions, Schimel argues. “Wisconsin chose the latter.”

Unions are free to offer fewer services to member and non- member employees in a particular workplace, the attorney general said.

“Beyond the duty of fair representation, the services provided by unions result from the union’s choice, not from any statutory obligation,” according to the state.

Walker, after fending off a union-backed recall, last year won a four-year court battle over 2011 legislation curbing the collective bargaining power of some public sector employees.

He was re-elected in November, defeating Democrat Mary Burke.

The case is Machinists Local Lodge 1061 v. State of Wisconsin, 15-cv-0628, Dane County, Wisconsin, Circuit Court (Madison).

To contact the reporter on this story: Andrew Harris in federal court in Chicago at aharris16@bloomberg.net To contact the editors responsible for this story: Michael Hytha at mhytha@bloomberg.net Andrew Dunn