Q: Are the litigants and/or witnesses required to stand before the beis din?
A: The Torah states: “The two people who are the litigants should stand before the …. judges” (Devarim 19:17). We derive from this that both the litigants and witnesses should stand; the witnesses when testifying and the litigants when the decision is rendered.
During the proceedings and claims, the beis din can ask the litigants to stand or give them permission to sit, but must treat both litigants equally, both standing or both sitting. A Torah scholar coming before beis din should be respected and allowed to sit, together with his litigant. Some maintain that the litigants should not sit until they are granted permission by the beis din.
If the witnesses or litigants did not stand as required, the testimony and ruling is valid, regardless. Nowadays, it is customary that batei din ask the litigants and witness to sit throughout (C.M. 17:1-3; Pischei Teshuvah 17:4; Aruch Hashulchan 17:5).