Hi Aspirant,
You are good to go if you are talking about PhD in law.You can easily apply if you have a postgraduate degree in law with above  55%grade or of candidates appearing in final exam are also welcome to apply but if you are talking about PhD in other subjects then it will create a big problem since it requires devotion to academic qualities and also a post graduate certificate of that very subject in initial degree.Plus a complete shift from what you will do and what you are doing will also create a problem.If you are pursuing law keep consistency ,success will strike your path.
All the best.