Civics: 75% in U.S. See Widespread Government Corruption (contemplate Government Schools)

Gallup:

These figures are higher than some might expect, and while the lack of improvement is somewhat disconcerting, the positive takeaway is that Americans still feel fairly free to criticize their government. This is not the case in some parts of the world. Questions about corruption are so sensitive in some countries that even if Gallup is allowed to ask them, the results may reflect residents’ reluctance to disparage their government. This is particularly true in countries where media freedom is restricted.

This is why it is most appropriate to look at perceptions of corruption through such lenses as the Freedom House’s Press Freedom rankings. Ratings vary among countries with a “free press,” including the U.S., and range from a high of 90% in Lithuania to a low of 14% in Sweden. The U.S. does not make the top 10 list, but notably, it is not far from it.