Here are my South Dakota Statutes…note they conflict with each other.
32-20-4.1. Eye protective device or windscreen required--Violation as petty offense. No person may operate a motorcycle unless he is wearing an eye protective device or unless the motorcycle is equipped with a windscreen of sufficient height and design so as to provide adequate eye protection to the operator when seated on the motorcycle in the normal operating position. However, no person may operate a motorcycle during the time period when headlights must be lighted while wearing an eye protective device that is tinted or shaded to reduce the light transmittance of the device to a level below thirty-five percent. A violation of this section is a petty offense.
Source: SL 1970, ch 176, § 3; SL 1984, ch 228, § 9; SL 1989, ch 255, § 105; SL 1989, ch 256, § 16; SL 1990, ch 255.
32-15-4. Glazing material on motorcycles--Violation as petty offense. On motorcycles the glazing material used in the windshield or wind deflectors shall be of a clear plastic type which need not be of an approved type. A violation of this section is a petty offense.
Source: SL 1953, ch 243, § 4; SDC Supp 1960, § 44.0102-1; SL 1977, ch 189, § 101.
32-15-2.7. Manufacturer certification of compliance with light transmission specifications. Each manufacturer of film, glaze, or other application for a motor vehicle windshield or window shall certify to the Department of Public Safety that the film, glaze, or application the manufacturer makes or installs complies with the light transmission specifications of §§ 32-15-2.4 and 32-15-2.5.
Source: SL 1989, ch 268, § 2; SL 1994, ch 257, § 3; SL 2004, ch 17, § 138.
32-15-2.9. Sunscreening devices on windshield prohibited--Extension of film limited. No sunscreening devices may be placed on or affixed to a windshield so as to obstruct or reduce the driver's clear view through the windshield. No film may be extended downward beyond the AS-1 line or more than the lowest point of the sun visor of the motor vehicle. A violation of this section is a Class 2 misdemeanor.
Source: SL 1994, ch 257, § 5.
32-15-2.4. One-way glass, adhesive film, or other glaze in windshield or front side windows prohibited--Violation as misdemeanor. No motor vehicle required to be registered in this state and which is operated on the highways of this state may be equipped with one-way glass or any adhesive film or other glaze or application on or in the front windshield, side wing vents, or side windows on either side forward of or adjacent to the operator's seat, which reduces the light transmittance of such windows to the combined level below thirty-five percent, with an enforcement tolerance of nine percent. A violation of this section is a Class 2 misdemeanor.
Source: SL 1988, ch 257, § 1; SL 1989, ch 255, § 231; SL 1994, ch 257, § 1.
32-15-5. Nontransparent material on windows prohibited--Petty offense--Official certificates excepted. It is a petty offense for any person to drive any vehicle upon a highway with any sign, poster, or other nontransparent material upon the front windshield, side wings, side, or rear windows of such motor vehicle other than a certificate or other paper required to be so displayed by law or temporary driving instructions placed thereon by the manufacturer unless the same shall not obstruct the driver's clear view of the highway or any intersecting highway.
Source: SDC 1939, § 44.0349; SL 1967, ch 199, § 1; SL 1977, ch 189, § 102.