For the most point, admitting to having done Y is strong evidence that the person did do Y so I’m not sure if it can generally be considered a bias.
In the case where there is additional evidence that the admittance was coerced, I’d probably decompose it into the Just World Fallacy (ie “Coercion is wrong! X couldn’t have possibly been coerced.”) or a blend of Optimism Bias and Typical Mind Fallacy (ie “I think I would never admitting to something I haven’t done! So I don’t think X would either!”) where the person is overconfident in their uncoercibility and extrapolates this confidence to others.
This doesn’t cover all situations though. For instance, if someone was obviously paid a massive amount of money to take the fall for something, I don’t know of a bias that would lead to to continue to believe that they must’ve done it
Bob’s reply is not concerned with the truth of whether X did Y in the Bayesian sense. Bob doesn’t argue about what the correct probability happens to be.
It’s concerned with dispute resolution. In a discussion about truth, wanting doesn’t matter. In a process of dispute resolution it matters a great deal.
For the most point, admitting to having done Y is strong evidence that the person did do Y so I’m not sure if it can generally be considered a bias.
In the case where there is additional evidence that the admittance was coerced, I’d probably decompose it into the Just World Fallacy (ie “Coercion is wrong! X couldn’t have possibly been coerced.”) or a blend of Optimism Bias and Typical Mind Fallacy (ie “I think I would never admitting to something I haven’t done! So I don’t think X would either!”) where the person is overconfident in their uncoercibility and extrapolates this confidence to others.
This doesn’t cover all situations though. For instance, if someone was obviously paid a massive amount of money to take the fall for something, I don’t know of a bias that would lead to to continue to believe that they must’ve done it
Not generally but I notice that the argument I cited is usually invoked when there is a dispute, e.g.:
Alice: “I have strong doubts about whether X really did Y because of...”
Bob: “But X already admitted to Y, what more could you want?”
Bob’s reply is not concerned with the truth of whether X did Y in the Bayesian sense. Bob doesn’t argue about what the correct probability happens to be.
It’s concerned with dispute resolution. In a discussion about truth, wanting doesn’t matter. In a process of dispute resolution it matters a great deal.