How is investigation of Modi by "Supreme court of India" an independent investigation? It is the classic case of "we looked into our wrong doing and found nothing"
“How is the investigation of US president trump by the US congress an independent investigation…?”
I mean - fair point, it's not.
Are they independent if going against him means you most likely will lose your job next election cycle?
Now, it is entirely fair to argue that that the powers in question are colluding in some way. But most states that haven't been subverted into authoritarianism have multiple actors with the power and (sometimes) will to investigate other ones.
I mean, if you take that argument far enough, no human could judge any other human, because none of them are "independent".