Q. If a Beis Din strongly suspects that the defendant in a very significant monetary litigation is not telling the truth, but they can't prove it, can they demand that the parties should be subjected to a lie detector test?
A. Horav Shlomo Miller's Shlit'a opinion is that it is preferable that the Beis Din demands that defendant should take an oath or shevuas chesses, (an oath enacted to discourage defendants from denying claims that lack sufficient evidence. Shevuos 40b - Shulchan Aruch, C. M. 87:1).
If that is not a good option as the defendant who is not religious, may be suspected of making a false oath or not caring if others do so in his name, the Beis Din may demand a lie detector test.
Rabbi A. Bartfeld as advised by Horav Shlomo Miller and Horav Aharon Miller Shlit'a
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