The article directly states in its first paragraph that the list originates from a government source:
> This is a list of states and union territories of India ranked by incidents of human trafficking as of 2016, and is based on the number of convicted cases. The list is compiled from the '2016 Crime in India Report' published by National Crime Records Bureau (NCRB), Government of India.[1]
Of course this kind of data has its own issues (e.g. incidents that don't end in a conviction because of bribery or police/judicial misconduct or that don't get caught by police at all don't end up in it), but it's probably the qualitatively best data you can get.
> This is a list of states and union territories of India ranked by incidents of human trafficking as of 2016, and is based on the number of convicted cases. The list is compiled from the '2016 Crime in India Report' published by National Crime Records Bureau (NCRB), Government of India.[1]
Of course this kind of data has its own issues (e.g. incidents that don't end in a conviction because of bribery or police/judicial misconduct or that don't get caught by police at all don't end up in it), but it's probably the qualitatively best data you can get.