Of course it's irrelevant. The whole purpose of having hearings is to provide a convenient anchor point for the news cycle, so the narrative can remain fixated on gun control. All their previous anchor points failed to achieve new gun control: Fast & Furious, Aurora, Newtown. So George Zimmerman is simply the new one. They will never stop at their effort to disarm the American citizen, because their vision for America requires a citizenry wholly subjugated to the will of the State.
Then of course you have sh*theads like John McCain providing them phony Right cover by making similar statements about so-called Stand Your Ground laws needing to be looked at.
Just what is a Stand Your Ground law anyway? It merely affirms that if you are somewhere you have the right to be, doing something you have the right to do, then the onus is not on you when confronted by a violent aggressor.
