Concerning the question Why does double jeopardy not apply to impeachment?, which I closed as a duplicate —
The Constitution does not allow citizens to be tried for the same crime twice except for impeachment, what was the reasoning of Framers for allowing this exception?
While the clauses dealing with impeachment and trial were written by the framers, the Fifth Amendment's double jeopardy clause was written by Congress, only some of whom were framers. Thus, when the framers wrote the Constitution there was no consideration of double jeopardy, nor any exception from, because there was no Fifth Amendment. Therefore, "what was the reasoning of [the] Framers for allowing this exception?" apparently has no answer.
While not an exception, Hamilton, in Federalist 66 suggests —
The division of them between the two branches of the legislature, assigning to one the right of accusing, to the other the right of judging, avoids the inconvenience of making the same persons both accusers and judges; and guards against the danger of persecution, from the prevalency of a factious spirit in either of those branches. As the concurrence of two thirds of the Senate will be requisite to a condemnation, the security to innocence, from this additional circumstance, will be as complete as itself can desire.
In a comment, it is stated the questions are very different.
I've voted to reopen this question because the other question asks "does double jeopardy apply," whereas this question asks "why doesn't double jeopardy apply," which is a very different question.
While I find the question in its current form is unanswerable, I nonetheless pursued the question of "why" and dug a bit deeper.
During consideration of what was to become the Fifth Amendment, an exception for impeachment was raised in the House.
Madison’s version of the guarantee [against double jeopardy] as introduced in the House of Representatives read: "No person shall be subject, except in cases of impeachment, to more than one punishment or trial for the same offense." — Fifth Amendment Development and Scope
But the Senate used different language for the part of the Fifth Amendment referring to double jeopardy, removing the exception for impeachment. Unfortunately, the Senate, at that time, met in secret, meaning there is no record of "the reasoning of [the] Framers for allowing this exception", or they may not have allowed for such an exception, or allowed that it may have been understood to be an exception.
Were the question reopened, the absence of a Senate record would suggest the question should be closed again as speculation or opinion.
Should I reopen the question or should some other action be taken?