Full Idea
The testimony of a number of independent witnesses, none of them particularly reliable, who give substantially the same account of some event, may provide a strong argument in its favor.
Gist of Idea
Several unreliable witnesses can give good support, if they all say the same thing
Source
Timothy McGrew (Evidence [2011], 'Testimonial')
Book Reference
'Routledge Companion to Epistemology', ed/tr. Bernecker,S/Pritchard,D [Routledge 2014], p.66
A Reaction
A striking point. It obviously works well for panicking people in a crowd during an incident. Does it also apply to independent scientists who are known to cheat? They may not collaborate, but may all want the same result.