From their technical methodology note[1], they require their data sources to account for "state capture" and the usage of "public office for private gain". Take that as you wish, and feel free to look further at their sources[2]; however, I'd assume from that statement that they do account for lobbying and donations.

The US is not unique. If you see something happening here, it is almost always happening in other western countries, and acting like we are the only to have a problem does a disservice to worldwide development.

[1] http://files.transparency.org/content/download/2183/13748/fi...

[2] http://files.transparency.org/content/download/2183/13748/fi...

> I wonder if the index treats lobbying and donation millions to support elections as corruption. Such activities are illegal and considered corruption in most countries.

Lobbying has nothing to do with donating money, and lobbying elected representatives is definitely not illegal in most democracies.

Good question. I have to admit that I haven't read their methodology yet.