Section 257.642 - Roadway divided into 2 or more marked lanes; applicable rules; designation as HOV lane; restrictions; exceptions; designation as automated vehicle roadway or lane; violation as civil infraction(1) If a roadway is divided into 2 or more clearly marked lanes for traffic, the following rules in addition to all other rules that are consistent with this act apply: (a) A vehicle must be driven as nearly as practicable entirely within a single lane and must not be moved from the lane until the operator has first ascertained that the movement can be safely made.(b) On a roadway that is divided into 4 or more lanes and provides for 2-way movement of traffic, a vehicle must be operated within the extreme right-hand lane except if overtaking and passing, and must not cross the center line of the roadway except if making a left turn.(c) On a roadway that is divided into 3 lanes and provides for 2-way movement of traffic, a vehicle must not be operated in the center lane except under any of the following circumstances:(i) If overtaking and passing another vehicle traveling in the same direction, and the center lane is clear of traffic within a safe distance.(ii) In preparation for a left turn.(iii) If the center lane is allocated exclusively to traffic moving in the same direction the vehicle is proceeding and the allocation is designated by official traffic control devices.(d) Official traffic control devices may be erected directing specified traffic to use a designated lane or designating those lanes to be used by traffic moving in a particular direction regardless of the center of the roadway and operators of vehicles shall obey the directions of the traffic control device.(e) Official traffic control devices may be installed prohibiting the changing of lanes on sections of roadway, and operators of vehicles shall obey the directions of the traffic control devices.(2) If a lane is designated as an HOV lane by an agency with jurisdiction over the roadway, and is appropriately marked with traffic control devices, the lane must be reserved during the periods indicated for the exclusive use of buses and HOVs. The restrictions imposed on an HOV lane do not apply to any of the following: (a) An authorized emergency vehicle.(b) A law enforcement vehicle.(3) If a segment of roadway is designated as an automated vehicle roadway or a lane or ramp of an automated vehicle roadway as an automated vehicle roadway lane under section 665c, both of the following must apply:(a) If a user fee is required under section 665c(1)(c), the user fee is paid.(b) The motor vehicle or automated motor vehicle complies with any applicable requirements of section 665c(2).(4) The requirements of subsection (3) apply in addition to other existing rules or regulations governing the use of an automated vehicle roadway or automated vehicle roadway lane that are not inconsistent with subsection (3).(5) An individual who violates this section is responsible for a civil infraction and may be fined as provided in section 907.Amended by 2023, Act 148,s 1, eff. 10/10/2023.Amended by 2022, Act 179,s 2, eff. 7/25/2022.Amended by 2012, Act 498,s 18, eff. 3/28/2013.Amended by 2008, Act 304,s 3 , eff. 12/9/2008.1949, Act 300, Eff. 9/23/1949 ;--Am. 1974, Act 289, Imd. Eff. 10/15/1974 ;--Am. 1978, Act 510, Eff. 8/1/1979.