By definition a legal framework is not a social contract. Technically there IS a social contract that we will agree to follow the laws, but not everyone does that one either. We violate speed limits, download media, burn crosses in front yards.

There are also many cases where laws do not cover the violations of a social contract. Slurs are protected speech under most circumstances, but that does not mean that there are no consequences to utilizing them in your vocabulary in public. You will never go to jail for it, but in using them you violate a social contract of tolerance, and thus the members of society around you should not tolerate your presence. If you pull a gun while using those slurs, that is a clear indicator that you intend harm, specifically on the people to whom the slurs refer. This violates the social contract of safety, which means that you are open to being harmed yourself by the members of the contract around you. They protect the safety of the members by preventing you from harming them. It is actually covered in the US laws and has been condoned by society. The "murder is wrong" tautology fails very quickly in the face of reality. Is it OK to kill someone who is actively raping an infant? How about if they have a knife to your partner's or child's throat? What about if they point a loaded gun at a crowd of unarmed protestors and are not a legally recognized peace officer? Your moral code determines where that line is, but everyone has a line. Do you condone Israel's actions against the Palestinians? Let's go for the good ole trolley problem. Do you pull the lever? Is that OK?