Courtroom Commandments?

I have found that most of the people who say the 10 commandments should be displayed in law courts usually do not know what the 10 commandments are. The reason people who are not christian have problems with the 10 commandments is they are *not* a universal code of law as many try to claim. In fact the first four are all about which god to worship and how to worship him. Those first four thereby are irrelevant to anyone who does not worship the christian god. As that throws out nearly half the total right there I do not see how anyone can make a good argument that they belong in the court rooms of a country that declares everyone should be free from religious persecution.