Currently, if you try to sabotage other nation's spies it will show as "Spies Captured" in your nation screen. I think this is a bad idea since you can't really preform the act without people quickly finding out who did it. With login times, active times, and just seeing how many you capture each day. It's quite easy to figure out your Spy Sabotage operations.
My suggetion is to remove from public viewing the Spy Captured and Spy Lost information. Because why would my spies tell the world how many people they captured?