In my Twilight Impirium group we included an optional rule called "Interrogation" tactics. When you have captured an opposing leader. You may choose to Interrogate him as an action for one strategy allocation and roll on the following table
1-The leader Skillfully escapes his torturers and is returned to his owner on a planet of his choosing
2-3 The strain of the torture proved to much for the leader, and he is killed.
4-The leader endures the "interrogation" and divulges no information-Nothing happens
5-6:The leader divulges some minor infornation that could be used to sabotage an enemy's plan
You may randomly discard an action card from the leader's owner
7-The leader cracks and provides some information regarding their plans.
you may look at your opponents hand of action cards and discad a card of your choice
8-The leader divulges information that may very well be used against his race
You may randomly take an action card from the Leader's owner
9-He leaks major information that could be devastating to his race
10-The leader truly breaks and is completely brainwashed, he follows your every command
The leader, for all purposes counts as a leader of your race and may be placed on any planet under your control
You may interrogate a leader up to two times, and only once per game round.
recieve +1 on the roll if you have any of the following-A trade contract with the owner. You control a leader that originally belonged to the Leader's owner, you pay 3 trade goods.
Recieve +2 if you are the leader's original controller