McBruce, on Jul 12 2004, 10:05 PM, said:
As far as I am aware, the only thing that could possibly apply here is the Rule of Coincidence. There is no Law compelling you to double based on what partner has shown. The most you can be hit with under the RoC is an adjustment in the number of tricks if the opponents have made a play that is based on your bidding. Look for the Rule of Coincidence on a search engine and you'll find something on point here.
However, the RoC is specifically not meant to apply to any but the clearest of situation where one partner has psyched, or made a non-system call, and the other partner has distorted his values to compensate. In this case, as other posters have pointed out, the auction itself tells you that there is a good chance that partner has psyched.
The "Rule of Coincidence" is something that came up in the ACBL years back - and according to my quick research on rec.games.bridge there currently is no such rule, and may never have been. In any case, an ACBL rule wouldn't apply to BBO, with the exception of ACBL run tourneys.
In any case, in the given auction, clearly someone has psyched, or a pinochle deck has made its way to the table. Even at your first call, holding 10 hcp, with the various other players promising 12+, 15-17, and 10+... let's see... 47+! Already your partner is the favorite to be the psycher, given that he has a passed hand partner. You clearly didn't allow for your partner to have psyched - with your redouble and double of diamonds, and your partner had ample opportunity to double himself and didn't do so. The auction and your hand make it clear that your partner has psyched, you don't have to be suicidal