RAPID CITY, S.D. (AP) - U.S. Senator Tim Johnson has co-sponsored a bill that he says will help reduce gasoline prices.

His measure would increase federal oversight of the oil and gas industry in an effort to prevent market speculation that Johnson says is helping drive up fuel costs.

The legislation would ask the Energy Department to stop buying oil for the Strategic Petroleum Reserve, which is 97 percent full.

The bill would allow the Justice Department to take action against foreign nations for illicit practices in setting oil prices and limiting oil production. It also would impose a windfall profits tax on large oil companies if they do not invest a certain amount of earnings into expanded production capacities.

Johnson says oil companies have not put their record profits into more exploration and production but instead have purchased stocks and returned record dividends to stockholders.

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