Understanding Bias-Based Traffic Law Enforcement:
A Manual To Reduce Bias-Based Traffic Law Enforcement

Understanding Bias-Based Traffic law Enforcement


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Traffic Enforcement

Community Outreach

Data Collection


Legislation and Case Law


Death, injuries, and economic losses from traffic crashes constitute the number one health problem in many industrialized countries. It is paramount that we collectively and comprehensively pursue the task of reducing this public health crisis as one of our most basic commitments.

As law enforcement officials, we are obligated to provide safe highways and streets for our motoring public, but this does not require bias-based law enforcement. Law enforcement officers should not consider a person’s race, ethnicity, national origin, religion, gender, disability or sexual orientation in deciding which drivers are subjected to a traffic stop, search, or other post-stop action. An exception is where officers are on the lookout for, or are seeking to stop, detain, or apprehend one or more specific persons who are identified or described in part by these characteristics.

The law enforcement agency’s chief executive is responsible for putting in place procedures for monitoring and assessing the conduct of his/her officers on traffic stops, and he/she should also be prepared to respond to questions from the public and the media regarding these matters. Some suggested methods include, but are not limited to, data collection on race, ethnicity, and gender, citizen satisfaction surveys, sampling techniques, the use of in-car video systems, an effective citizen complaint system, and supervisory oversight.1

  1. Conducting Professional Traffic Stops
    Many law enforcement officers and community members have identified “routine” police-citizen encounters (for example, traffic stops) as a source of potential conflict and tension between law enforcement officers and members of the public, especially where residents in the community believe that law enforcement action is being taken based, in part, on racial stereotypes or bias. To the officer, traffic enforcement contacts are routine, but for the motorist, such contacts are fraught with emotion. Officers should be aware of this and should strive to make each instance educational, leaving the motorist with an understanding that the officer has performed a necessary task in a fair and professional manner.

  2. Preventing Bias-Based Traffic Stops
    Officers need to make traffic stops based on existing traffic or criminal law violations. Pretextual stops are often sensed by the violator and may evoke a negative reaction. For instance, safety belt checkpoints can be excellent examples of community policing, saving lives, public education and police visibility. Law enforcement agencies also use checkpoints to deter impaired driving and to ensure highway safety in addition to occupant protection. If the motorist senses that this checkpoint is to detect impaired drivers, as opposed to checking for safety belts, it may turn into a negative situation.

  3. Conducting Fair Traffic Enforcement
    The guarantee of equal protection to everyone is a fundamental principle of our society. To protect this essential right, law enforcement agencies should adopt policies to ensure that officers perform their duties in a non-discriminatory manner. Criminal activity transcends race or ethnicity. Law enforcement officers should not rely on generalized stereotypes, attitudes or beliefs about the propensity of any racial, ethnic, or national origin group to engage in unlawful activity. There is no allowable trade-off between effective law enforcement and the protection of the civil rights of all Americans; we can and must have both.

Agencies should have a clear and widely disseminated policy prohibiting differential treatment on the basis of race, ethnicity, national origin, religion, gender, disability, or sexual orientation in the performance of law enforcement duties.

Agencies should mandate that law enforcement personnel receive clear and thorough training throughout their career to address these issues. Additionally, agencies should be prepared to explain their policies on non-discrimination, use of force, search and seizure, and other areas of citizen interaction.

II. Promoting Accountability and Effective Management

Studies of law enforcement agencies have yielded empirical data that a small number of law enforcement officers are responsible for a disproportionate amount of problematic police behavior. Many law enforcement agencies have developed personnel management databases (often called “early warning” systems) to identify problem behavior and allow early intervention to correct that behavior. Generally, these systems are non-punitive, because the intervention prompts a peer review, counseling or additional training, and not formal discipline.

The long-term objective of this type of system is to create a culture of accountability in the agency. Several agencies that have developed early-warning systems have experienced significant reductions in complaints against officers and a reduction in complaint-based litigation.

III. Maintaining the Legitimate Rights of Law Enforcement Officers

Law enforcement officers have statutory rights. No officer should be subject to an unfair investigation of alleged misconduct. Any employee accused of misconduct has a right to be informed of the allegations; to have interrogations conducted at a reasonable time, place, and manner; and to have legal representation at a formal disciplinary hearing.

Such protections, which are noted in the law enforcement officers’ bill of rights in many states, are no impediment to the effective investigation of alleged officer misconduct.2

One aspect of the obligation to serve our communities is to ensure that agency procedures and actions are reasonable and effective. To fulfill this responsibility, agencies should provide a readily accessible process in which community and agency members can have confidence that complaints against agency actions and procedures will be given prompt and fair attention. Such investigation will not only provide for corrective action when appropriate, but also will protect against unwarranted criticism when actions and procedures are proper. A fair and thorough investigation also serves to protect the community, the agency, and its personnel from complaints that are based on misunderstandings or inaccurate information.

  1. Principles for Promoting Police Integrity, Examples of Promising Police Practices and Policies (U.S. Department of Justice, January 2001) pp. 15-16.
  2. Walker, Samuel, The Maryland Law Enforcement Officers’ Bill of Rights: A Barrier to Police Accountability, University of Nebraska at Omaha, January 2001.


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