No law is good simply because it exists. Think about it; nearly 100 years ago, women were not recognized as 'persons' until the Persons Act. African-American men and women could not ride horses or enter certain establishments before the civil war. As was mentioned, under the command of the 3rd Reich, the Jewish people were lawfully discriminated against, robbed, evicted, tortured and murdered. Biblical law states that if a man rapes a woman, the appropriate punishment is that he marries her...which actually still happens today. And on a slightly more controversial note, marijuana and other drugs remain illegal despite their contribution to organized criminal activity.
I am by no means saying that all laws are bad; that would be stupid. We as people do our best to build rules to help everyone as best we can, and these rules are constantly modified and changed...or at least they are supposed to be. That is the shining beauty of democracy: nothing is eternally set in stone. Different people can change wrong or ineffective laws as they see fit.
Of course, this also goes the bad way. When our laws are based upon public perception, bad things are bound to happen. A PERSON can be sharp, level headed and logical; PEOPLE are inevitably doomed to be stupid, panicked and illogical.