Why should Christians care about ethics?

A:We should all care about ethics and try to act ethically. There is no reason for Christians to be exempt from practising high moral values.

Another Answer:

Ethics usually refers to a societies well-founded 'standards' of what is right and wrong - telling its citizenry what they can and cannot do without fear of consequences - perhaps the primary reason for these societies to be ethical.

Though most Western governments have an ethical approach of law based upon several inputs, it was particularly in the USA, where its founding fathers used The Bible as its guide to develop its Constitution. At the time, America was primarily a Christian nation.