Because the founders did not trust the judges, prosecutors or others with administative justice
When it come to a group of people, I believe white men were able to vote first, then in 1869 woman were able to vote, while non-white and free male slaves were able to vote in 1870. But if your asking a person I honestly don’t know who! Sorry if this ain’t what you had asked for!
I am not sure but I think is 22%