Can you give an example of a President publicly releasing criminal evidence against a rival candidate in order to influence a Presidential election?
The closest I can think of is perhaps the Mueller report, but that happened under Trump and was ordered by Obama after the election specifically to avoid influencing it.
Trump is the only modern President I can think of that has even publicly accused an election rival of a crime from the White House, but again, his disregard for norms of the office and laws such as the Hatch Act is abnormal.
They never released the "evidence" before the election because everyone expected Hillary to win. It was done post-election to undermine his presidency.
I think trying to prosecute Trump to keep him off the ballot was a worse disregard of norms.