The U.S. Department of Justice secretly spies on millions of cars by gathering and storing information about motorists in order to build a national database to track movements, according to a new report in the Wall Street Journal. The database was originally used by the Drug Enforcement Administration to hunt vehicles involved in drug crimes by tracking license plates, but according to the WSJ, the program expanded to hunt for criminals sought for crimes that were non-drug related. DEA officials have been on record saying they track vehicles near the U.S.-Mexico border to help fight drug cartels, but the new...