Hello 

University in India conducts it own styled Ph.D. Entrance Test ( PET), you have to keep searching the websites of all University. After clearing that PET, you become eligible to be admitted for Ph.D., subject to availability of guide and your interview before RAC ( Research Allocation Committee). If you have already cleared NET/ Having industrial experience/ M.phil, then in that case you may claim and get an exemption from appearing in PET, but you have to apply for that.

Hey Sujitkumar

A PhD in Law involves research and an academic approach to Law study. A PhD in Law is not to be confused with a Juris Doctor, which is a professional degree preparing students to practice. ... Through coursework, teaching, and research, candidates for a PhD Law degree will complete a dissertation to be awarded the degree.

I Hope It Helps 

Good Luck