[hiAndrewQuinn]

Would you necessarily know if they were successful? Can you actually prove that not a single person in that convention accepted some kind of kickback for e.g. changing their vote?

Mechanisms that effectively prevent this do exist in the literature, to be clear, but I rarely hear of those ones actually getting implemented.

[namlem]

Well we mostly know what positions these groups were pushing for. It's possible that some influence went unnoticed.

That said, the US used to have quite a lot of juror bribery in the late 1800s and managed to successfully crack down on it with harsh penalties, sting operations, and other strategies. Attempting to bribe a juror can get you 15 years in federal prison in the US, it's not taken lightly.