I am all for upholding the law but in this case in particular, it is clear that the agencies have tried VERY hard to find something to pin on her. Moreso because she was already guilty in the eyes of the majority(because of the patriarchal mindset).
She has been arrested for procuring weed for her boyfriend, which is wrong I agree, but since when has NCB started arresting people for 50 grams marijuana? If that would have been the case then half of India would have been in jail.
I am not saying she is a saint, but what she has been accused of, people in India have done way worse and walked away freely. And the reason why she has been such an easy scapegoat is because of the patriarchal mindset- where an independent, modern woman in a live in relationship with her more successful boyfriend is looked upon as a gold digger witch.
IMO, this arrest has less to do with "upholding the law" and more to do with appeasing the people. Murder nahi, money laundering nahi, abetment nahi toh marijuana sahi. If its upholding the law, then start performing raids on bollywood, politicians, all the saadhus and start taking them into custody for not just marijuana but many other drugs. But that wont happen.