Detroit News 
April 2, 2011
The U.S. Secret Service said today that some federal vehicles for law enforcement and security purposes will be exempt from President Barack Obama’s directive that all federal vehicles purchased starting 2015 be advanced technology models.
Secret Service spokesman Robert Novy said the directive wouldn’t apply to vehicles used for some law enforcement or security reasons by various federal agencies.
“Certain specialized vehicles including those with law enforcement and security specifications are not subject to this directive,” Novy said.
That would include the GM-built Cadillac presidential limousine and other vehicles in the motorcade. It also expected to include many law enforcement vehicles.
Obama announced the plan this week to “green” the federal fleet.