People who participate in certain activities that are bad for society are disqualified from testifying. Also, those who've commit certain sins whose punishment is corporal, and haven't yet repented, ...
Let's say I use the pretty much disproven Techelet (Radzyner) : is my Tzitzit completely Pasul? I think according to the Arizal it isn't. Does anyone disagree?
Is a man who masturbates invalidated as a witness? The Gemara in Sanhedrin (26b) states that prohibited sexual relations do invalidate his status as a witness, but I could not find any literature on ...