Firing squad hell. I have a very dull hatchet and I volunteer to do the job. Might take a while, but it'll get done.
I think you both are taking the wrong approach. The absence of the death penalty increases the chance of them being found guilty. Besides, we Conservatives can actually win over the liberals by not being as vindictive. That's why I am recommending something that does not include capital punishment for the leaker.
I would highly recommend either:
Ten years hard labor in the gas chamber
OR
Life in the electric chair on bread and water!
What do you think - is that going just a little too easy on them?
I think permanent disqualification from holding public office should be first. Then dispose of them as you will.