Lay judge
Defined in 2 dictionaries — Ballentine's (1916), Black's (1910)
Ballentine's Law Dictionary
James A. Ballentine · 1916
A judge not versed in law.
Black's Law Dictionary
Henry Campbell Black, M.A. · 1910
A judge who is not learned in the law, i. e., not a lawyer; formerly employed in some or the states &a assessors or assistants to the presiding judges in the nisi prius courts or courts of first instance.
Defined under Lay in Black's Law Dictionary.