Traffic Regulations

Everybody has an equal right to use the public streets for purposes of travel, by proper means[i].  But the right to use the public streets is not an absolute and unqualified right.  It is subject to limits and control by the sovereign authority, the state, whenever necessary[ii].

The regulation of motor vehicles on the public highways is a legitimate exercise of the police powers of a state[iii].  Pursuant to such power, the state may make all reasonable laws, rules, and regulations for the safety and protection of the public[iv].

The power of the legislature to regulate the operation of motor vehicles includes the power to enact legislation affecting the reciprocal rights and duties of all who use them, whether s/he is an owner, operator, or occupant[v].

State law with respect to vehicles and traffic will be applicable and uniform throughout the state and in all political subdivisions and municipalities in the state[vi].

A city or local authority may enact its own traffic laws, as long as they do not conflict with the provisions of the state law unless expressly authorized by statutes[vii].

Jurisprudence related to preemption and conflict in the context of traffic violations are distilled by the courts into four main points of law[viii]:

  • state law preempts the field of traffic law except for that which is expressly permitted by state statute;
  • no conflict exists when an ordinance is merely additional and complementary to a state law and covers specifically what the statute covers generally;
  • municipalities must provide the same procedural protections as the state when prosecuting offenses that are covered by an ordinance and a statute; and
  • a municipality may not prohibit by ordinance conduct that is not prohibited by statute.


The State, in the exercise of its police power, may regulate the speed of automobiles and provide other reasonable rules and restrictions as to their use.  Statutory regulation of the speed of machines while running on highways is reasonable and proper for the promotion of the safety of the public[ix].

Some jurisdictions expressly authorize a city to regulate traffic by means of police officers or traffic-control signals[x].  State laws give permission to local authorities to place and maintain traffic control devices upon highways under their jurisdictions to indicate and to carry out the statutory provisions or to regulate, warn, or guide traffic[xi].

The driver of an automobile approaching or passing a school has a statutory duty to proceed with extreme care and with the automobile under control, provided that the authorities have legible and visible signs posted to warn drivers of their approach to the school[xii].

State statutes impose a duty upon a motor vehicle operator to comply with any lawful order or directive of any police officer invested by law with the authority to direct, control, or regulate traffic, irrespective of the instructions or signals of a traffic control device[xiii].  A motorist will be relieved of liability for causing an accident if s/he acted in accordance with directions of a traffic control officer.

A vehicle should be driven upon the right half of the roadway upon all roadways of sufficient width.  Statutes prohibit an operator of a motor vehicle to drive his/her vehicle left of center, unless an exception exists under statute[xiv].

Further, vehicles are permitted to travel on the roadways and not on the paved shoulders, emergency lanes, or within other paved areas that are divided from the roadways, except in particular instances such as when an emergency exists[xv].

Statutes place criminal liability on those who operate a vehicle left of center and  provide that upon all roadways of sufficient width, a vehicle or trackless trolley should be driven upon the right half of the roadway, except as follows[xvi]:

  • When overtaking and passing another vehicle proceeding in the same direction or when making a left turn under the rules governing such movements;
  • When an obstruction exists making it necessary to drive to the left of the center of the highway; provided, any person so doing should yield the right of way to all vehicles traveling in the proper direction upon the unobstructed portion of the highway within such distance as to constitute an immediate hazard;
  • When driving upon a roadway divided into three or more marked lanes for traffic under the rules applicable thereon;
  • When driving upon a roadway designated and posted with signs for one-way traffic;
  • When otherwise directed by a police officer or traffic control device.


In some jurisdictions it has been judicially determined that a lower standard of care should be exacted where the carriage in any type of vehicle is gratuitous[xvii].

[i] State v. Mayo, 106 Me. 62 (Me. 1909).

[ii] Silver v. Silver, 108 Conn. 371 (Conn. 1928).

[iii] State v. Mayo, 106 Me. 62 (Me. 1909).

[iv] Harkrider v. Posey, 2000 OK 94 (Okla. 2000).

[v] Silver v. Silver, 280 U.S. 117 (U.S. 1929).

[vi] Loyal Tire & Auto Ctr., Inc. v. Town of Woodbury, 445 F.3d 136 (2d Cir. N.Y. 2006).

[vii] State v. Greene, 97 Wn. App. 473 (Wash. Ct. App. 1999).

[viii] State v. Kuhlman, 729 N.W.2d 577 (Minn. 2007).

[ix] Commonwealth v. Kingsbury, 199 Mass. 542 (Mass. 1908).

[x] State v. Kuhlman, 729 N.W.2d 577 (Minn. 2007).

[xi] State v. Lee, 265 Neb. 663 (Neb. 2003).

[xii] Northup v. Gage, 6 A.D.2d 748 (N.Y. App. Div. 4th Dep’t 1958).

[xiii] Theriot v. Bergeron, 939 So. 2d 379 (La.App. 1 Cir. June 21, 2006).

[xiv] State v. Tague, 676 N.W.2d 197 (Iowa 2004).

[xv] Payne v. State, 275 Ga. 181 (Ga. 2002).

[xvi] State v. Leichty, 68 Ohio St. 3d 37 (Ohio 1993).

[xvii] Silver v. Silver, 280 U.S. 117, 123 (U.S. 1929).

Inside Traffic Regulations