I choose to believe that rather than all being part of some anti-City, pro-United conspiracy referees are people, subject to the same vagueries of opinion and ability to err as we all are. I don't know what inspired Clattenburg award the penalty, perhaps he genuinely hates City, perhaps his pre-match shower was the wrong temperature, maybe he's a racist....I don't know.
But, and here's the killer evidence. If he was corrupt then he would have to be the most mindblowingly, bewilderingly stupid person to walk the face of the planet given that his 'corrupt' act was witnessed by millions of people and that he chose to express his bias in the least subtle manner imaginable...a truly corrupt person would surely have at least attempted something with a little more guile?