The person or persons (such as jurors or judges) who consider evidence in a legal proceeding and make determinations on assertions of fact.(noun)
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Use "fact-finder" in a sentence
"When the Obamacons come for you, hola, I am sure they will ask a fact-finder to review your case and determine whether you are actually a danger or just another whackjob."
"Fact One: Most of the prisoners in Gitmo have never had a neutral fact-finder determine whether they actually represented a threat or did whatever deed they are accused of."
"To misinterpret the demeanour of a witness is always a danger, but it is a particular danger when the fact-finder is confronted with a witness belonging to a different culture …"