SDCL § 32-12-46: Cause for suspension or revocation of license--Notice and examination--Failure to submit to examination--Issuance of restricted license.

The Department of Public Safety, having good cause to believe that a licensed driver is incompetent or otherwise not qualified to be licensed, may, upon written notice of at least five days to the licensee, require the driver to submit to an examination or interview. Upon the conclusion of the examination or interview the department shall take action as may be appropriate and may cancel the license of such person or permit the retention of the license, or may issue a license subject to restrictions as permitted under §§ 32-12-36 and 32-12-37. Refusal or neglect of the licensee to submit to the examination or interview shall be grounds for cancellation of the license.