I would not believe everything Zig says. Spanier's lawyers have instructed him NOT to speak about the issue, so chatting with Zig would certainly be on the No No List.
I agree 100% that Ziegler can be a complete ass. However, I have yet to catch him telling any deliberate lies about the case. Whenever he engages in speculation, he admits its just that and he does openly retract theories when it seems that are not supported by the evidence (such as the possibility that Aaron Fisher was actually molested by his stepfather).
I was the first person to suggest to Ziegler that the McQueary incident may have occurred prior to February 9, 2001. He was actually extremely skeptical at first. It was only after he was presented with a flood of facts that he decided to change his views.