>>/6740/
> double jeopardy,
That exists in a certain (criminal) context - you cannot be charged for the same crime twice. There are some exceptions - notably a person being charged in State or Federal court. Now, wither respect to POTUS - even the impeachment inquiry is not a trial, it's an investigation. IF evidence is found of 'high crimes or misdemeanors' then the House can vote to impeach. Then it would go to the Senate for an actual trial.
In this sense, the trial in Senate would be for a single or list of separate crimes, which obviates the premise of double jeopardy.