Just read the NYTimes article about the Lamine Diack's son allegedly taking bribes to swing the Olympic vote.
https://www.nytimes.com/2017/10/16/sports/olympics/papa-massata-diack-iaaf.html
I just don't really see how the bribes work unless the whole voting system is rigged as well.
Let's say Rio wants the Olympics and pays Mr X $10 million for "consulting" to bring them to Rio.
Mr X can go to the various countries and bribe them as well and say here's $500,000 vote for Rio.
But what's to stop another city say Salt Lake City from going to Mr X and saying here's $10 million, bring us the Games? In a private voting system, there is no way to see if the bribery is effective and the guy taking the bribes could be taking them from both sides. How does he effectively prove he's bringing votes in return for the bribes?
Or were the votes somehow comprised? The Times piece has this, " On the same day as the vote, Diack transferred about $300,000 to Frankie Fredericks, a former sprinter from Namibia and rising star of the Olympic movement who happened to be one of three people scrutinizing the vote." Are there allegations the votes weren't counted properly?
But unless votes in the past were public I don't see how the bribery is effective unless it's just a trust thing.