The feds just started a five-day Saint Patrick's Day weekend crackdown on drunk drivers.

The National Highway Traffic Safety Administration is warning drivers that if they're impaired-- they'll be arrested.

Wisconsin, Minnesota, and four other Midwestern states are affected.

The feds say it's a response to a recent study on drinking and driving.

The research shows half the drivers and motorcycle riders involved in deadly crashes last Saint Patrick's Day had a blood-alcohol level above legal limits.