Responsa על שבועות 63:22

Q. A claims that his representative caused him to lose his case against B by willful neglect, for the representative pleaded in court those arguments which A asked him not to plead, and neglected to plead those arguments which he specifically asked him to. A, therefore, demands that his representative compensate him for the loss caused him.
A. If A lost money through his representative's willful neglect, the latter must make good A's loss. But, if the case is such that had the representative pleaded A's arguments, A would have had to swear and be able to recover, or swear and be free from obligation, and now the case is that the oath has either been transferred to B, or that now B may collect without taking an oath, the representative is free from obligation, since the damage to A's interests is not clear and remains problematical, as no one can be sure that A would have taken the required oath. However, if the case is such that had the representative pleaded A's arguments, A would be free from obligation and would not be required to take an oath, and now B collects from A without being required to take an oath, the representative is guilty of willful neglect.
SOURCES: Cr. 157; Pr. 242; Mord. B. M. 290; Rashba I, 1106.

Q. A claims that his representative caused him to lose his case against B by willful neglect, for the representative pleaded in court those arguments which A asked him not to plead, and neglected to plead those arguments which he specifically asked him to. A, therefore, demands that his representative compensate him for the loss caused him.
A. If A lost money through his representative's willful neglect, the latter must make good A's loss. But, if the case is such that had the representative pleaded A's arguments, A would have had to swear and be able to recover, or swear and be free from obligation, and now the case is that the oath has either been transferred to B, or that now B may collect without taking an oath, the representative is free from obligation, since the damage to A's interests is not clear and remains problematical, as no one can be sure that A would have taken the required oath. However, if the case is such that had the representative pleaded A's arguments, A would be free from obligation and would not be required to take an oath, and now B collects from A without being required to take an oath, the representative is guilty of willful neglect.
SOURCES: Cr. 157; Pr. 242; Mord. B. M. 290; Rashba I, 1106.