Idaho is latest battle ground in national right-to-work struggle. Labor calls for repeal of law barring mandatory union dues

National labor leaders and the National Right to Work Committee have their eyes fixed on Idaho, where voters in November will determine the outcome of a ballot referendum on the state's right-to-work law. If history is any indication, the law, which makes it illegal for an employer to require a worker to pay dues to a union in order to keep a job, stands about a 50-50 chance of being upheld by Idaho voters.

The law was passed in 1985 by the Republican-controlled Legislature over the veto of Democratic Gov. John B. Evans. Idaho unionists have challenged the law in court on a variety of reasons and collected 60,000 signatures to force a voter referendum this fall.

Union critics of the right-to-work law argue that it will lower wages by enabling employers to hire nonunion workers. Organized labor also contends that the law will encourage workers to ``free-load'' by not paying dues to the unions representing them at the bargaining table.

Proponents say the law will help attract new industry to breathe life into Idaho's sagging economy. And they say workers should not be forced to join unions whose politics or practices they may not condone.

In 1958, a similar law was narrowly defeated on the ballot in Idaho, winning 49 percent of the vote.

Union members make up only about 17 percent of Idaho's work force, but with help from national unions they were able last year to put more than $200,000 into a campaign in opposition to the right-to-work law.

AFL-CIO director of information Murray Seeger said recently that the Idaho referendum is ``very important to us. An attack in Idaho is an attack on all of us.''

Mr. Seeger said right-to-work laws attack the sanctity of contracts because they render illegal union security clauses agreed to at the bargaining table.

The national debate over the right-to-work concept goes back to 1947, when Congress passed the Taft-Hartley Labor Relations Act over President Harry Truman's veto. It gave states the right to prohibit the so-called ``closed shop'' or ``union security'' agreements that allow unions to collect dues from all workers for whom they bargain. Federal law requires that unions represent all members of a work place, not just union members.

Twenty-one states now have right-to-work laws.

In 1985 right-to-work measures were on ballots in California, Colorado, Idaho, Kansas, Ohio, and Washington.

Only Kansas adopted such a law, according to information from the Right to Work Committee and from Idahoans Against Deception, an AFL-CIO-funded group working to convince voters not to approve the law.

Idaho right-to-work leaders say that if the state's voters reject the law in November, it will be a major setback for the movement.

Clayton Roberts, spokesman for the National Right to Work Committee, says plans are under way to move the fight to New Mexico. That state, Oklahoma, and Colorado have political climates that may be conducive to passage of right-to-work measures next year, Mr. Roberts says.