A recent investigation conducted by the Investigative Reporting Program at UC Berkeley and California Watch has found  DUI checkpoints in  California are more effective in increasing profits for a number of police departments than in catching drunken drivers.

According to reports, in 2009, many  checkpoints actually netted more car impounds from unlicensed drivers than arrests related to driving under the influence.  In fact, the number was up 53 percent from 2007.  The towing fees and police fines related to these impounds amounted to approximately $40 million dollars.  In addition, the crackdown on  DUIs generated an estimated $30 million in overtime pay to police officers.

The investigation also revealed the majority of these impounds involved minority drivers, many illegal immigrants.  It has been suggested this is due to police frequently conducting checkpoints in and around neighborhoods with a predominantly Hispanic population.  Whatever the reason, such impounds seem at odds with a 2005 federal appellate court ruling preventing the police from impounding cars solely based on the driver being unlicensed.