No matter how trustworthy someone is when they get elected, there is always a chance for them to become corrupt once in office. After all, before they've actually held public office, there's little to no incentive or opportunity to be corrupt—and the higher the office, the higher both become.

We need effective rules of ethics (with teeth) and oversight procedures. I don't think that forcing every politician to wear a camera 24/7 is really the best solution, but it's hopelessly naïve to think that some of them aren't literally going to bed with the people who are trying to get favorable legislation passed.

A society like the US is just too diverse—not so much in heritage, but in cultural values (or at least subcultural values) to be able to "just elect people who can be trusted."