Rule of thumb. If ever the government claims state secrets, they are playing their, "We did something wrong, and would like to get out of jail free" card.<p>I know of a number of cases where state secrets was claimed, then later it was proven that there was no actual state secret proven. (Including the very first case where state secrets were used as a defense in a court room.) I know of no cases where state secrets were claimed, and then there turned out to be an actual state secret at issue.