Dude, I think you're missing the whole point

From a letter in The Hindu:

Ajmal's trial is nothing but taking democracy too far. Only a person whose guilt is in doubt should be given an opportunity to defend himeself, not one who is is responsible for killing innocent people indiscriminately.

Pray tell, how do we decide that someone's guilt is in doubt or not, without going through the whole judicial process (a.k.a. 'trial')?