Indiana Code Title 3. Elections § 3-7-13-13

Sec. 13. (a) Except as provided in subsections (b) and (c), when an individual registers to vote, the individual must provide the individual's driver's license number issued under IC 9-24-11, as provided under 52 U.S.C. 21083.

(b) If an individual does not have a driver's license issued under IC 9-24-11, the individual must provide the last four (4) digits of the individual's Social Security number when the individual registers to vote, as provided under 52 U.S.C. 21083.

(c) As required under 52 U.S.C. 21083, if an individual does not have a Social Security number, the election division shall assign the individual a number to be associated with the individual's registration in the computerized list maintained under IC 3-7-26.3.  If the individual has an identification card number issued under IC 9-24-16, the election division shall assign that number as the voter's number under this subsection.  If the individual does not have an identification card number issued under IC 9-24-16, the election division shall assign a unique identifying number to the voter's registration record in the computerized list, as provided under 52 U.S.C. 21083.

(d) The number provided by the individual under subsection (a) or (b), or the number assigned to the individual under subsection (c), is the individual's voter identification number.

(e) A voter's voter identification number may not be changed unless:

(f) If a voter transfers the voter's registration and the voter's voter identification number is not included in the voter's registration records, the voter registration officer of the county in which the voter's registration is to be transferred shall require the voter to provide the number required by subsection (a) or (b) before the voter's registration is transferred.  If the voter does not have either of the numbers described in subsection (a) or (b), a voter identification number shall be assigned to the voter under subsection (c).