Purpose

Clarifies that optometrists may prescribe certain tinted window glazing materials for medical needs and creates specific exemptions to existing glazing restrictions in Minnesota law. The change aims to let prescriptions drive when and how tinted windows may be used in certain vehicles, while tying allowances to patient medical needs and documented limits.

Main Provisions

• Glazing material exceptions (new subsection 4a under Minnesota Statutes 169.71):

  • Subdivision 4 (the general rule on glazing materials) does not apply to glazing materials that are used to satisfy a prescription or medical need, as long as the following conditions are met (i–iv):
  • i. The prescription or a physician/optometrist statement of medical need is provided.
  • ii. The prescription specifically states whether the medical need is temporary or permanent.
  • iii. The prescription or statement specifies the minimum light transmittance percentage that may be reduced to meet the medical need.
  • iv. The prescription or statement includes an expiration date, which must be no more than two years after the prescription/statement date unless the physician/optometrist indicates the condition is permanent and no expiration date is appropriate.
  • The exemptions also apply to certain vehicle windows listed below (see “Scope”).

• Scope of exemption (specific vehicles and windows):

  • Rear windows of a pickup truck (as defined in state law).
  • Rear windows or the side windows behind the driver's seat of a van.
  • Side and rear windows of a vehicle used to transport human remains by a licensed funeral establishment.
  • Side and rear windows of a limousine.
  • Rear and side windows of a police vehicle.

• Use by a driver when the prescription is not held by the person present:

  • A driver may rely on a prescription or medical need statement issued to a person who is not in the vehicle if:
  • i. The prescription is issued to a close relation or designated caregiver (e.g., the driver’s parent, child, grandparent, grandchild, sibling, or spouse, or a person for whom the driver is a personal care attendant).
  • ii. The prescription specifies the make, model, and license plate of one or two vehicles that will have tinted windows.
  • iii. The driver possesses the prescription or statement.

• Compatibility with Federal standards:

  • The exemptions reference original installations or replacements that were installed or replaced in conformity with Federal Motor Vehicle Safety Standard 205, and are used to meet prescription/medical needs, subject to the above requirements.

How this changes current law

• Creates a targeted exception to a general glazing restriction, allowing optometrist-prescribed tinted glazing in specified circumstances and vehicle types.
• Establishes a formal process for medical authorization, including duration (temporary vs permanent) and a defined minimum light transmittance limit.
• Limits exemptions to particular vehicle types and windows, and adds a mechanism for using prescriptions issued to others (with conditions) to cover situations where the driver is not present.
• Ties allowances to compliance with FMVSS 205 where applicable.

Practical Implications

• For patients with medical needs requiring reduced glare or privacy, optometrists can authorize specific window tinting in certain vehicles, with documented limits on how much tinting is allowed.
• Law enforcement and funeral service vehicles have explicit permission windows, acknowledging their unique use cases.
• Clinicians and drivers must maintain clear prescriptions with expiration dates and the required technical details (minimum light transmittance, vehicle identifiers).
• Potential safety considerations include ensuring that tinting remains within medically prescribed limits and that prescription details are readily available if requested by authorities.

Significant changes to existing law

• Adds a clearly defined medical-prescription pathway for glazing materials that previously might have faced stricter limitations.
• Establishes concrete expiration and certification requirements for prescriptions.
• Specifies vehicle and window categories eligible for the exemption, creating a narrow, controlled expansion rather than a broad allowance.

Relevant Terms

• glazing materials
• light transmittance
• prescription
• physician
• optometrist
• medical need
• temporary vs permanent
• expiration date
• Federal Motor Vehicle Safety Standard 205 (FMVSS 205)
• rear windows
• side windows
• pickup truck
• van
• funeral establishment (funeral transport)
• limousine
• police vehicle
• make, model, and license plate (vehicle identification)
• personal care attendant