 In United States v. Sun @-@ Diamond Growers of California ( 1999 ) , the Supreme Court held that the gratuity statute required a nexus to an official act , but not a quid pro quo . Both past and future official acts are cognizable , but not payments for status , access , generalized goodwill , or unspecified acts . Sun @-@ Diamond defined the nexus as follows : " We hold that , in order to establish a violation of 18 U.S.C. § 201 ( c ) ( 1 ) ( A ) , the Government must prove a link between a thing of value conferred upon a public official and a specific ' official act ' for or because of which it was given . " 
