IT WILL BE DIFFICULT TO BE IMPARTIAL.

Once a president always a president. Senator Patrick Leahy has no authority under a "non president" waiver for impeachment after office to preside over the impeachment trial of President Donald John Trump because the president does not fall under a "non president" category of persons. He remains a president forever. The waiver is meant for those other officials below the president who may have committed acts of corruption in office and wanted to evade prosecution by resigning their office. 

The purpose of a president's impeachment is to end his presidency forthwith and stop him from continuing in office which purpose is defeated once a president is no longer in office. It is an aberration for a president who is no longer in office to be subjected to an impeachment trial for acts done while in office and for which there is no longer his existing presidency to remove him from. Congress lost that fight when the president completed his term of office and left because  impeachment is meant to remove a president from office not to punish him thereafter. The matter of impeachment of President Donald John Trump is therefore moot. 

Further, being a member of the charging party, Patrick Leahy is a party adverse to the president and cannot seat in judgment over President Donald John Trump because he cannot guarantee the president a fair trial. Democrats cannot be the judge, the jury and the executioner in the matter of impeachment of the president. They raised the issue against the president, they indicted the president, they are pursuing a trial of the president, they will prosecute the president by themselves and a Democrat is the chief presiding officer or judge. 

It is a constitutional violation of the president's due process rights to fair hearing that the same Democratic Party accused the president of a crime, indicted the president for the crime, will prosecute the president for the crime and will also seat in judgment over the president for the same crime. The Supreme Court should intervene as a matter of constitutional imperative to end the charade of trying a president who is no longer in office for an act done during his presidency for which impeachment is no longer an available post presidency remedy or punishment. Simply an overreach.