Shemuel being extra-careful to ensure rights of orphans in a Bill: Ketuvot 21a
Cases
The judges in Neherdaa, and Rav Chana bar Bizna in Pumbedita, using movable items from a deceased father's estate to support his daughters, and Rav Nachman ordering them to reverse their decision as erroneous: Ketuvot 50b
Rav Nachman told Rav Chana Bar Bizna to reverse a verdict on which money had been collected, or he would collect it from Rav Chana himself: Bava Kama 12a