The President has the authority to investigate alleged instances of corruption abroad involving US persons.
We have a treaty to handle such requests and not one of the provisions in that treaty is for a public announcement of an investigation of any US citizen. Even if there was evidence, a coerced public announcement by the President of the country is not in the provision either.
Whether or not Trump used a criminal amount of "leverage" to investigate the issue, is also irrelevant.
Both parties agreed to the appropriation of the aid. The President was using that aid to attack one party. There is nothing on the books that call that action a crime but imo, it was a corrupt political act worthy of removal from office.
Did Trump commit corrupt political act? Yep.
Did Biden commit a corrupt political act? Yep.
And as Hillary would say: "What difference it make," and I'd agree with her on that one if she said it.
Politics is a dirty business, which is why Jesus Christ got crucified...Jesus was too clean of man to be a politician and survive. Impeachment isn't for sweeping away the daily dirt of political activity, it's for stopping mudslide that destroy our Federalist Republic.
If the courts decided on impeachment, every United States politician that ever lived, is living and will live, would be convicted and removed from office. That is why the courts don't decide impeachment cases. A political body does (the Senate).
The Senate requirement is 2/3, since a simple majority vote would lead to INSTABILITY since virtually every President would be impeached and removed from office.
You're advocating for the proverbial "Pandora's Box," where everyone impeaches and investigates and removes everyone from power in legalized civil war. Our system would collapse within a year and descend it a literal shooting civil war of far right and far left warlords.
Is this what you want?