He did his post-graduation (Master of Science) in Chemistry from Punjab University, Chandigarh.

This was followed by his Ph.D. thesis in fluorine chemistry, which was highly commended and resulted in 15 research publications of a technical nature, in international scientific journals of repute.

[3] Paul has experience working in the Intelligence Bureau (IB) and the Research and Analysis Wing (RAW).

[3][4] He was the longest serving Police Commissioner of Delhi from February 2004 to July 2007.

This challenged Narendra Modi's government's attempts to make Governors appointed during the UPA regime resign.