Let’s say that two people are blamed for breaking the vase. In the tale of suspect 1, the order of events was A, B, C. In the tale of suspect 2, the order of events was A, B, D.
Given that the two suspects each have a motive to lie and will tell the story that favors themselves the most, we shouldn’t expect their stories to line up unless that portion is true. Subsequently, we don’t know what happened after B but we are confident that both A and B are true.
I could consider this to be a form of “multiple attestation” or, I suppose, “independent sources” but it’s very common in modern Internet debate to be working with partisan sources and the target audience to be a member of one of those partisan groups. It’s a stronger technique for that specific situation than simple multiple attestation and “independent sources” usually implies neutrality on the part of the witnesses.
Is there a commonly accepted term for this specific case?