I was thinking the Clintons. Nixon and Johnson combined couldn't touch them with a ten foot pole when it comes to crimes in office. I believe that Hillary is still leading the pact of criminals in high places.
I read a book, I think the Author was Cato, but can't remember for sure, about Johnson. He was an interesting character. He was crooked from childhood. Also a physical coward.
When he stole his Senate seat, he was aided by Harry Truman, that icon of modern Democrats, and sadly, many Republicans.