when all you have is hate, you act hateful.
Whether or not it's truly justifiable, I have my own set of rules for this particular subject.
I find it very disrespectful to the families involved when one does this. That being said, I had no problem expressing my sentiments regarding John McCain... the difference being that John McCain himself politicized his own death, and then his family proceeded to do the same after he actually died. I know it seems like self-justification, but I won't bring it to the table.... but if they do, they waive their rights to courtesy.
Dumpasses, on the other hand, revel in the moment when they get the opportunity... and I find them to be sub-human because of it. The dead person can't hear you... but their family can, and a civilized human understands that quite clearly.