Yes, prostitution should be legal. Prostitution will always exist; like with abortion or certain drugs, you have the choice to legalize and regulate or to allow dangerous activity to happen when it doesn't have to.
1. There should be a separation of church and state according to our constitution, and the sinfulness of prostitution is a religious concept. Just because your holy book says that society should not include prostitutes does not mean that you have a right to impose your beliefs on everyone.
2. The benefits of legalization are myriad. If prostitution were legal:
a. Women who were forced to do it could avoid being prosecuted.
b. The government could garner revenue.
c. The market for sex slaves would be reduced.
d. Prostitutes would be less vulnerable to abuses by pimps.
3. All of these benefits are sacrificed in order to not encourage prostitution. However, our culture encourages prostitution plenty already. Anyone can secure a prostitute with the push of a button.
4. Law enforcement should be concerned with crimes that actually harm other people, of which there are plenty of followers.
5. With institutional racism and economic sluggishness, there really are few job options for some people.
Why do we want to control others' lives so much? Why can't we all be free to try to survive in whatever way we can? Legalize it for goodness' sake.