The Manual on Uniform Traffic Control Devices (MUTCD or Manual) has been at issue in many tort actions against transportation agencies by motorists, bicyclists, or pedestrians for a transportation department’s alleged violation of one or more provisions of the Manual. The extent of a transportation agency’s tort liability differs from state to state because of the lack of uniformity of state tort claims acts and other relevant statutes and judicial interpretation of the same. Transportation agencies thus need to be aware of the effect of the MUTCD on their potential liability in tort under their own state’s laws.

Larry W. Thomas, Effect of MUTCD on Tort Liability of Government Transportation Agencies, Legal Research Digest

Role of the MUTCD in Legal Matters

The MUTCD is the national standard for traffic control devices (TCDs). It is owned, administered, and revised by the Federal Highway Administration (FHWA).

Federal regulations establish the Manual on Uniform Traffic Control Devices (MUTCD) as “the national standard for all traffic control devices installed on any street, highway, or bicycle trail open to public travel” (23 USC 655.603).

FHWA gives the MUTCD a significant amount of importance, respect, and authority, indicating that the MUTCD is:

  1. A standard used by road managers nationwide
  2. A publication containing national standards governing all TCDs to bring uniformity in the application of TCDs
  3. Critical to providing safety and mobility of motorists on highways
  4. The law governing all TCDs.

States’ Responsibilities with Using the MUTCD

States have several responsibilities when it comes to the MUTCD, including:

1. Adopt the MUTCD or Manual in Substantial Conformance

Each state must adopt an MUTCD for that state and the basis for the MUTCD is defined in each state’s transportation law. A state has the option of:

  • Adopt the federal MUTCD as its MUTCD (as 18 states, such as Arkansas do),
  • Adopt the federal MUTCD with a state supplement (22 states, along with Puerto Rico and DC, take this approach), or
  • Develop and adopt its own state MUTCD (10 states, including Texas, have developed state manuals)

A state supplements or state MUTCD must be in “substantial conformance” with the federal MUTCD and must be approved by the FHWA prior to adoption. When the MUTCD is revised or updated, States have two years to adopt the new version, or adopt an updated State MUTCD.

2. Comply with New Standards

When changes in the MUTCD apply to existing TCDs in the field and are deemed to be of critical safety importance, states are given compliance dates for updating devices. The current MUTCD provides target compliance dates in Table I-2 of the introduction.

If a compliance date isn’t provided, FHWA notes that:

“Each State, in cooperation with its political subdivisions, is required by Federal law (23 U.S.C. 402(a)) to have a program for the systematic upgrading of substandard traffic control devices and for the installation of needed devices to achieve conformity with the MUTCD. The program should include dedicated time to properly assess traffic control operations and needs, budgeting of funds required for implementing MUTCD changes and, to the extent possible, and accomplishing the changes either when the devices are no longer serviceable because they reach the end of their service life or otherwise need to be replaced, or when other events such as highway improvement or reconstruction projects occur.” (FHWA MUTCD site FAQs Page, October 2011 )

3. Use the MUTCD

State and local transportation engineers and planners use the MUTCD to inform the design, placement and construction of TCDs. The MUTCD provides mandates of varying levels that inform this process (See Item Number 4 on Using the MUTCD).

The MUTCD states:

“The decision to use a particular device at a particular location should be made on the basis of either an engineering study or the application of engineering judgment.  Thus, while this Manual provides Standards, Guidance, and Options for design and applications of traffic control devices, this Manual should not be considered a substitute for engineering judgment.  Engineering judgment should be exercised in the selection and application of traffic control devices, as well as in the location and design of roads and streets that the devices compliment.”  (MUTCD Section 1A.09)

The importance placed on a qualified traffic engineer to make sound engineering judgments in the selection and implementation of TCDs cannot be overlooked or dismissed.  There are infinite varieties of roadway and intersection designs and there is no “one size fits all” mentality in the application of TCDs.  The proper use and application of the MUTCD starts with the decisions made by a qualified traffic engineer. 

MUTCD and Tort Liability

“The MUTCD is the law governing all traffic control devices. Non-compliance with the MUTCD ultimately can result in the loss of federal-aid funds as well as in a significant increase in tort liability.” (FHWA MUTCD site Overview Page, October 2011)

Failure to follow the MUTCD by a road authority (or contractor working for a road authority) may expose the road authority or contractor to liability if a crash occurs and a lawsuit is filed alleging improper use of or failure to install a TCD contained in the MUTCD. The logical argument is:

  • The traffic control device in place was inappropriate or the MUTCD required a different traffic control device
  • The improper device or lack of the “required device” caused the crash to occur
  • The road authority or contract failed to perform the duties required by the MUTCD and is responsible for the crash

There are other engineering-related issues that become relevant in litigation related to the MUTCD.  Was the person selecting the TCD qualified to do so? Was good engineering practice applied in making the traffic engineering decision? Is the allegation of an MUTCD violation relevant to the case?

The potential for an agency or facility owner to be sued for failing to comply with MUTCD provisions is one of the primary enforcement mechanisms related to the MUTCD, as there is no “MUTCD Police Department” that is responsible for identifying violations of the MUTCD.  Due to it frequently being cited as a factor in tort liability, practitioners often interact with attorneys on MUTCD issues related to a specific lawsuit.  These interactions may be as an expert or as a witness for the agency/owner to explain prior decision-making related to specific TCDs.  The following considerations are worth acknowledging in the course of these interactions:

  1. While the national MUTCD is defined as the national standard for TCDs, the content within the MUTCD contains various levels of mandate, not all of which is a standard or required practice.
  2. Traffic and engineering laws vary by state and can impact the practice of traffic engineering and the implementation of TCDs.
  3. The specific MUTCD criteria related to a crash that occurred on a specific date depends upon the state version of the MUTCD that was in effect at the time of the crash, the date of installation of TCDs and the MUTCD that determined the criteria for those devices, and the traffic laws that were in effect at the time of the crash.
  4. TCDs alone may not be able to correct deficiencies created by other factors such as inappropriate roadway design, improper driver behavior, or unique/unexpected circumstances.

Despite the extensive amount of content in the MUTCD, the document is not able to address every possible TCD situation that may occur in the field. Practitioners may need to make TCD decisions that conflict with or are beyond the scope of MUTCD content. This is why the MUTCD states that it is not a substitute for engineering judgment.

For More Information

Please refer to TRB’s National Cooperative Highway Research Program (NCHRP) Legal Research Digest 63: Effect of MUTCD on Tort Liability of Government Transportation Agencies.

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