Thou shalt not
The Supremes have ruled on the presence of the Ten Commandments on government property.The long and the short of it appears to be pretty vague. It seems that it depends (go figure) on the whole display in context. For example, it it is the only thing featured on three walls of a courtroom - that might be construed as an unconstitutional endorsement of a religion. However, it you have a statue on the courthouse grounds among other statues of historical nature, that would be viewed as taking a historical perspective. It is along the lines of "how we got here" rather than "who we are." Kinda sorta adrift in the vagaries of all of this.
I sorta kinda agree with the ruling though. It is vague enough to please me, I guess.
I am not overly religious. I believe in God, but I don't believe anybody has a right to query me about it. I live my life by a certain code, but I don't enforce my beliefs on anybody else. I find those pushy born-again people offensive.
However, there is no question that this country was founded by people of a decidedly Christian bent. The puritans were not Buddhist or Muslim. These are our roots and they can not be denied. Now, this doesn't mean that we are still Puritans - but it does bear on our national conscience of right and wrong.
For example, some religions wouldn't find some violent sex crimes to be illegal when the US justice system does. Is it wrong to prosecute the criminal if it isn't a crime in his eyes? No, of course not. He gets his day in court, just like all the other rapists. But, if he can't convince a jury of his peers that it was not a crime, he must do the time. That's the way the system works.
I wouldn't be offended if a Koran was in a courtroom, so why should somebody be offended if a copy of the Ten Commandments is present? I don't know. But I can see where the size and the nature of the display have some relevance to the issue. So, I'm willing to see how some might be offended.
However, I can tell you this: people get offended everyday and they manage to survive it. Even me.