Indiana Code Title 6. Taxation § 6-1.1-5-10

Sec. 10. If a township assessor, or the county assessor if there is no township assessor for the township, believes that it is necessary to obtain an accurate description of a specific lot or tract, the assessor may demand in writing that the owner or occupant of the lot or tract deliver all the title papers in the owner's or occupant's possession to the assessor for the assessor's examination.  If the person fails to deliver the title papers to the assessor at the assessor's office within five (5) days after the demand is mailed, the assessor shall prepare the real property list according to the best information the assessor can obtain.  For that purpose, the assessor may examine, under oath, any person whom the assessor believes has any knowledge relevant to the issue.