What is a doctor of juris prudence?

A "juris doctor" (or J.D.) is essentially the professional doctorate degree for those lawyers and attorneys. This is awarded after earning a bachelor's degree, receiving entry into an appropriate law school and completing approximately 3 years of intense study of relative law and legal issues. It is similar in nature to the M.D. awarded to medical practitioners or the Ph.D. awarded to those in other fields (i.e. clinical psychology) who complete their professional training after completing their bachelor's degree. It is the doctorate needed to be a lawyer. Just thought they are uneducated! The JD is the doctorate received to become a lawyer/attorney. The PHD is the doctorate for the fields of study not covered by JD or MD. We don't call lawyers "doctor" why do we need to call those who have received a PHD in education "doctor"?