A Phoenix-based think tank is accusing the city of Tucson of violating state law with an ordinance aimed at helping local businesses. The Arizona Daily Star reports the Goldwater Institute is threatening legal action if the city does not repeal the ordinance, which allows contracts to be awarded to local companies even if those businesses are not the lowest bidders. The group claims such action is illegal. The ordinance was passed last year and allows the city to grant contracts to area businesses that offer up to five-percent higher than the lowest bid. Proponents say it helps the community by keeping the money in the local economy, but the Goldwater Institute says it allows local officials to dole out contracts to special interests at the expense of taxpayers.