Sanhedrin 23: Choosing the Judges on a Beit Din; Disqualifing Judges/Witnesses

Perek II begins with a new Mishna.  It teaches that in cases of monetary law, three judges must be chosen where each litigant chooses one judge and then they agree on the third or those two judges choose the third.  Perhaps judges can be disqualified, particularly if they are not qualified to judge or if they are a relative of the litigant.  There is also the question of whether or not one litigant can disqualify the others' witnesses.  

Like today's best mediation processes, the rabbis made every attempt to ensure that a beit din was made up of judges who were agreed upon by the litigants.  The rabbis discuss whether or not there should be any limitations on this arrangement.  For example, how much should we be concerned about the qualifications of the judges?  The rabbis go into great detail describing the possible problems that could arise based on this type of decision-making.  They clearly wish to avoid bias.

Next, the Gemara examines whether or not judges could be disqualified.  Are there any circumstances under which a judge should step down?  What if one suggests that the other's father should be one of his judges?  The Gemara considers how careful the judges must be to ensure that they are able to judge justly regardless of the other judges on the beit din.  

The Gemara focuses on the question of disqualifying witnesses for some time.  This is more complicated, for witnesses need not be educated nor otherwise prepared for their role.  Further, it would require two witnesses to obligate a judgement like payment or taking an oath.  The rabbis continue their questioning due to a concern regarding witness tampering.  They offer a number of examples where litigants might claim to have different numbers of witnesses.  At the end of our daf, an example questions when witnesses are actually necessary and when other evidence, like a document, will suffice.