What is the test for an award under section 2412(d)(1)(A) of the Civil Procedure Act?

The Act authorizes attorney fees and expenses for prevailing parties in civil litigation involving a government agency unless the court finds that the agency's position was "substantially justified or that special circumstances would make an award unjust." 28 U.S.C. Sec. 2412(d)(1)(A). The test is one of reasonableness. To defeat an award, the government must show that "its case had a reasonable basis both in law and in fact." Hoang Ha v. Schweiker, 707 F.2d 1104, 1106 (9th Cir.1983).