Do we need ethics if we have laws? Why or why not?

Ethics are essential because laws arise out of ethical choices. According to Vincent Ruggiero, in his book Thinking Critically About Ethical Issues (2011), ethics can be defined as the "study of right and wrong" (as cited by Polytechnic School). Laws develop when one person or a group of persons decide that some action, such as sexual harassment, is wrong. However, as Ruggiero asserts, just because laws arise from ethics does not necessarily mean that "every law is morally right." Laws change over time as our senses of right and wrong change; therefore, ethics must always be a constant guiding force to determining laws. One example of a law changing over time as our sense of ethics has changed concerns the practice of homosexuality. Multiple countries have had sodomy laws, which make the practice of homosexuality illegal. In England, sodomy was historically called buggery and first decreed a felony with the Buggery Act of 1533, making buggery a crime punishable by death ("Gay Rights Movement," Encyclopaedia Britannica). After James Pratt and John Smith were executed in 1835, Parliament enacted the Labouchere Amendment to make buggery a crime punishable by two years of jail time ("Pratt & Smith--Last UK Men Hanged for Sodomy," Peter Tatchell Foundation Speaking out for Human Rights). After a substantial increase in arrests of homosexual men after World War II, the government issued an investigation into homosexuality published in the Wolfenden Report in 1957 ("Wolfenden Report," Encyclopaedia Britannica). Committee members overseeing the report determined that homosexuality should no longer be considered a crime.Many examples of laws changing over time, such as women's suffrage laws and civil laws, further show that laws will always need to be guided by our sense of right and wrong. As our views of right and wrong change, our laws change too.
http://faculty.polytechnic.org/gfeldmeth/4.ruggiero1.pdf