Nogeia b’davar, is how you say in elegant Hebrew that someone is biased or interested in a matter in such a way as might affect their judgment. For example, “obviously he shouldn’t be on the search committee for the job he wants — he’s nogeia b’davar.” Nogeia is also used to mean “relevant”, as in “that question is simply not nogeia to the subject”.
The phrase is Talmudic in origin: Sanhedrin 34a talks about an interested witness who must be disqualified because he is “nogeia b’edut”. A related Talmudic phrase is “adam karov l’atzmo”, meaning literally, a person is related to himself. Relatives of the accused in a legal case cannot be witnesses. The accused himself, as his own closest relative, cannot do so either.
The word nogeia itself means to strike or afflict (negaim is leprosy.) This has a more forceful sense than the words “bias” or “interest”. Bias is literally an oblique line. “Interest” (interestingly enough) come from an Old French word meaning loss or damage. The Hebrew nogeia b’davar suggests that the default setting of a person is to be truthful in their judgment. The implication is that one dramatic event or circumstance is necessary to disturb a person from taking an honest, impartial view of a situation.