Condorcet's jury theorem states that given a group of voters (a "jury") independently choosing by majority vote between a correct outcome with probability and an incorrect one with probability :
1. If (so that each voter is more likely to vote correctly that incorrectly), adding more voters increases the probability that the majority chooses correctly and the probability of a correct decision approaches 1 as the number of voters increases;
2. If (so that each voter is less likely to vote incorrectly than correctly), adding more voters decreases the probability that the majority chooses correctly and the probability of a correct decision is maximized for a jury of size one.