I'm not a leftist, but I don't think that leftists are any more (or less) prone to corruption than anyone else. Corruption is part of human nature, and it is something that needs to be actively fought by all sides, and we should be unhappy with corruption on all sides. Personally, I get more angry at corruption in my own party (Republican) than I do with the other party. I have little respect for the other party, so I expect them to be corrupt. I expect my party to not be corrupt.