From the Washington Post:
The U.S. government has been increasing its use of the state secrets privilege to avoid disclosure of classified information in civil lawsuits, prompting legislation in the Senate that would provide more congressional oversight of the practice.
Though there have been modest increases in the use of the state secrets privilege every decade since the 1960s, some legal scholars and members of Congress contend that the Bush administration has employed it excessively as it intervened in cases that could expose information about sensitive programs.
Chart of published cases showing how government use of the state secrets privilege has grown over the past 35 years.