A Biblical sense of sin helps here: in this world sin will always be undermining even the best of human endeavours. There is no such thing as a world without corrupt bureaucrats.
The best we can hope for is to restrain evil. Eradicating it will be done by God someday (soon?); I don't think legalizing pot will do the trick.
Indeed. But we can minimize the damage they cause to all of society. One way is eliminating their jobs. Private-sector bureaucrats are bad, but not nearly as dangerous nor as expensive in terms of taxes.
RE-legalization of pot will remove many temptations from them.
The less the gov't is allowed to mess with, the less corruption there will be.