321J.20A  Ignition interlock device — medical waiver.
  1.  The department shall adopt rules pursuant to chapter 17A establishing criteria to waive the requirement to install an ignition interlock device under this chapter if a person has a verifiable medical condition, as determined in accordance with the rules, that makes the person incapable of properly operating an ignition interlock device. The rules must align with the special exception provisions under 23 U.S.C. §164(a)(6).
  2.  Notwithstanding any other provision of this chapter to the contrary, if the department waives the requirement to install an ignition interlock device, the person is not required to install an ignition interlock device to receive a temporary restricted license.
  3.  A temporary restricted license issued to a person who received a medical waiver pursuant to this section shall only authorize the person to operate a motor vehicle as described in section 321.215, subsection 1, paragraph “a”.
2024 Acts, ch 1050, §9 – 11
Section effective January 1, 2025, and applies to driver’s license revocations under chapter 321J for which the underlying offense occurred on or after that date; 
2024 Acts, ch 1050, §10, 11
NEW section