I sure can, truman. Remember, I said CIVIL codes, not CRIMINAL codes. For instance, check out the codes of most PUBLIC universities in the United States: they prohibit the display of the Confederate flag. Not a crime, but a civil prohibition.
Okay, but not an enforceable law, just as there is not enforceable law against flying the Mexican or British flag above the US flag.
Bad taste, yes but not against the law.