42 U.S.C. § 5148

Nonliability of Federal Government

The Federal Government shall not be liable for any claim based upon the exercise or performance of or the failure to exercise or perform a discretionary function or duty on the part of a Federal agency or an employee of the Federal Government in carrying out the provisions of this chapter.

( Pub. L. 93–288, title III, § 305 , formerly § 308, May 22, 1974 , 88 Stat. 149 ; renumbered § 305, Pub. L. 100–707, title I, § 105(d) , Nov. 23, 1988 , 102 Stat. 4691 .)