Hot answers tagged lomdus
As @Fred basically notes in the comment, the "davar" in the pasuk which requires "al pi shnayim" is the actual event/act itself, not the myriad details and preconditions that enable it (e.g. soklin al hachazaka by incest). Further, it would be hard to apply an anan sahadi to a scenario that does not conform to normal human nature, such as murder.
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