Well, if the guy himself can send down judgements and I'm sure expect them to be followed, then he should abide by the rules too.
If he'd just said that Yes, I disagree but I have to abide by the judgement - then fine . . . but he did act above the law and so he got what he deserved . . .
It's not like the ten commandments were on HIS LAND - they were in a public place and he put them there KNOWING DAMN WELL about goverment promotion of religion . . . and that big-ass thing is definitely an advertisement.