3/ With the Supreme Court saying in one hand, the president has “presumptive" immunity for “official" acts and in the other providing no test or definition of what an official act is, coupled with one cannot use an act of the president as evidence of a crime, this circular logic effectively creates a position that has no legal accountability.
And if congress thinks they can impeach and convict, then they are mistaken. First of all, to impeach you will need to gather evidence