JEFFERSON CITY, Mo. (AP) — Right-to-work supporters are trying to derail an effort by labor leaders to ask voters whether Missouri should ban mandatory union fees and dues.

A lawsuit filed Friday in Cole County claims a summary of the referendum proposal has “embarrassing” grammatical errors and is unfair.

Missouri AFL-CIO President Mike Louis is trying to put a new right-to-work law to a vote in hopes voters will overturn it.

The law takes effect Aug. 28 but could be delayed if enough signatures are gathered for a public vote.

Republican Secretary of State Jay Ashcroft approved the summary. He said in a statement that the language is clear, concise and complete. Ashcroft also says people are “playing politics” with voters’ right to weigh in on issues.