Opponents of a transportation sales tax on Missouri's August ballot are challenging the summary and cost estimate that voters will see.
A lawsuit filed Thursday by the Missouri Association for Social Welfare contends the ballot wording is misleading and unfair and should be rewritten.
Supporters of the ballot measure described the lawsuit as a long-shot attempt to make the wording more confusing.
The proposed constitutional amendment would impose a three-quarter-cent sales tax for roads, bridges and other transportation projects. Lawmakers who placed the measure on the ballot project it will generate $534 million annually for state and local governments over the next decade.
The lawsuit says the cost estimate is insufficient because it could be higher. It says the summary fails to note that the use tax also would rise.
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