As of this edit 710 former federal prosecutors have signed a petition stating that if Trump were not a sitting president he would be found guilty of obstruction of justice.
Some may try to label this list as just a group of angry Democrats. But not only is this a bipartisan group of prosecutors, about 5/8 have gotten their start under Republican presidents.
Here is the break down showing how many signors have gotten their start under each president:
Bush I 103
Bush II 46
Reagan 159
Ford 50
Nixon 84
Eisenhower 2
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444
Obama 32
Clinton 93
Carter 115
Johnson 14
Kennedy 12
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266