Prof. Mahanta obtained his MBBS degree from Gauhati Medical College under Gauhati University, Guwahati, Assam, India, in 1994; Doctor of Medicine (MD) degree (Forensic Medicine) from the same institute in 2001 under the same university; Doctor of Philosophy (PhD) from the Srimanta Sankaradeva University of Health Sciences, Guwahati, Assam, India in 2021.

He was awarded Fellow of the Indian Association of Medico-legal Experts (IAMLE) at the 5th International Conference on Legal Medicine, Medical Negligence & Litigation in Medical Practice & 5th International Conference on Current Trends in Forensic Sciences, Forensic Medicine & Toxicology held at the International Centre Goa, India from 25th to 27th Feb '14. Also, the Award of Distinguished Fellowship of the Indian Congress of Forensic Medicine & Toxicology (ICFMT) was conferred in recognition & appreciation for outstanding contribution to the field of Forensic Medicine & Toxicology at the XIVth Annual National Conference of ICFMT held at SGT University, Gurgaon, India from 13th to 14th Nov '15 and also awarded the Fellow of the Indian Academy of Forensic Medicine and Toxicology in 2023.

Prof. Mahanta is the editor of the Modern Textbook of Forensic Medicine and Toxicology. He has also edited another book on research methodology, Medical Writing: A Guide for Medicos, Educators, and Researchers. Asia's most prominent medical publisher Jaypeebrother Medical Publishers Pvt Ltd, New Delhi, India, publishes both of his books.

He has attended more than 60 CMEs cum Conferences accredited by the Medical Council of India (MCI) at State, National & International levels. He also presented over 60 papers in different CMEs and Conferences accredited by MCI.

He has 80 published articles in peer-reviewed indexed journals of national and international repute to his credit on health research, medical education, and medico-legal issues arising from day-to-day medical practice. He has also contributed 58 textbook chapters to different textbooks. He has been a guest lecturer at different government and private institutions to train various officers and doctors on medico-legal issues, health research and medical education.

He is a life member of the Indian Academy of Forensic Medicine, Indo-Pacific Academy of Forensic Odontology, Indo-Pacific Academy of Forensic Nursing Science, National Foundation of Clinical Forensic Medicine, Indian Association of Medico-Legal Experts, Life member of Medico-legal Society of Assam, Indian Medical Association, Indian Congress of Forensic Medicine & Toxicology, Founder Member of Academy of Health Research and Medical Education, Academy of Health Professions Educators and was the former Joint Secretary (East Zone) of Indian Academy of Forensic Medicine, the largest Academic Organization of Forensic Medicine and Toxicology. He was the founder general secretary of the Medico-legal Society of Assam.