It is unlawful for any county clerk or deputy county clerk in this state to issue a marriage license when either of the contracting parties is under the age of sixteen (16) years, unless court consent is granted, and any marriage contracted in violation of this provision may be annulled upon proper proceedings.  T.C.A. § 36-3-105.  However, a marriage entered into in violation of this section is valid until set aside by a court.  The court has discretion whether to set aside the marriage, and the court is not required to declare the marriage void.  Further, cohabitation after attaining marriageable age may validate the marriage.  Keith v. Pack, 182 Tenn. 420, 187 S.W.2d 618 (1945).

When either applicant is under the age of eighteen (18), the parents, next of kin, guardian or party having custody of the applicant shall join in the application, under oath, stating that the applicant is sixteen (16) years of age or over and that the applicant has their consent to marry.  If the applicant is in the legal custody of any public or private agency or is in the legal custody of any person other than a parent, next of kin, or guardian, then such person or the duly authorized representative of such agency shall join in the application with the parent, next of kin, or guardian stating, under oath, that the applicant has their consent to marry.  This provision does not apply to applicants who are in the legal custody of the department of mental health and mental retardation. T.C.A. § 36-3-106.

Upon good cause, the judge of the probate, juvenile, circuit, or chancery court has the power to remove the restriction as to age, and to authorize the county clerk to issue a marriage license regardless of the age of the applicants.  T.C.A. § 36-3-107.