John Q. Public - From Wikipedia

John Q. Public is a generic name in the United States to denote a hypothetical member of society deemed a "common man." He is presumed to have no strong political or social biases relevant to whatever topic is at hand, and to represent the randomly selected "man on the street." The equivalent terms are John Q. Citizen and John Q. Taxpayer. Female equivalents include Jane Q. Public, or Jane Q. Citizen, Jane Q. Taxpayer, Jane Winecooler, and Ann Yone (from "anyone"). Roughly equivalent are Joe Six-pack, Joe Blow, and Joe Schmoe, implying a lower-class citizen (from the Yiddish schmo: simpleton). Similar terms for the common family can be Mr. & Mrs. John Q. Public, Mr. & Mrs. John Q. Citizen, or Mr. & Mrs. John Q. Taxpayer