Robert Mueller is investigated Donald Trump Jr. for meeting with a Russian who claimed to have dirt on Hillary Clinton. It really was a hoax and she used the ruse to get the meeting to lobby for a change in adoption laws. Seems really silly to be investigating this.
The Mueller investigation is very partisan. Here is chief Trump critic, Democrat Adam Schiff, in the same situation, only in this case he really is offered dirt on Trump from Russians, and he agrees to take it. Yet, no investigation by Robert Mueller. It was actually a prank phone call, but still he did attempt to collude. Listen below to hear Schiff attempt to collude with Russia: