The law would certainly allow them to do so:http://www.law.cornell.edu/uscode/18/793.html
However, for whatever reason, the Department of Justice almost never
uses 18 USC 793. (Maybe it's actually never; I'm not sure.)

Nope, there's at least one, the case in which a Navy intelligence
analyst sent a KH-11 picture of a Soviet aircraft to Janes:

 MORISON v. U.S , 486 U.S. 1306 (1988)
486 U.S. 1306
Samuel Loring MORISON
v.
UNITED STATES.
No. A-896.

June 2, 1988.

Chief Justice REHNQUIST, Circuit Justice.

Samuel Loring Morison was convicted in the District Court of two
counts each of espionage, in violation of 18 U.S.C. 793(d), (e)...