In July 2019, the Metropolitan Police Department (MPD) implemented new data collection methods that enabled officers to collect more comprehensive information about each police stop in an aggregated manner. More specifically, these changes have allowed for more detailed data collection on stops, protective pat down (PPDs), searches, and arrests. (For a complete list of terms, see the glossary on page 2.) These changes support data collection requirements in the Neighborhood Engagement Achieves Results Amendment Act of 2016 (NEAR Act).The accompanying data cover all MPD stops including vehicle, pedestrian, bicycle, and harbor stops for the period from July 22, 2019 to December 31, 2022. A stop may involve a ticket (actual or warning), investigatory stop, protective pat down, search, or arrest.If the final outcome of a stop results in an actual or warning ticket, the ticket serves as the official documentation for the stop. The information provided in the ticket include the subject’s name, race, gender, reason for the stop, and duration. All stops resulting in additional law enforcement actions (e.g., pat down, search, or arrest) are documented in MPD’s Record Management System (RMS). This dataset includes records pulled from both the ticket (District of Columbia Department of Motor Vehicles [DMV]) and RMS sources. Data variables not applicable to a particular stop are indicated as “NULL.” For example, if the stop type (“stop_type” field) is a “ticket stop,” then the fields: “stop_reason_nonticket” and “stop_reason_harbor” will be “NULL.” Each row in the data represents an individual stop of a single person, and that row reveals any and all recorded outcomes of that stop (including information about any actual or warning tickets issued, searches conducted, arrests made, etc.). A single traffic stop may generate multiple tickets, including actual, warning, and/or voided tickets. Additionally, an individual who is stopped and receives a traffic ticket may also be stopped for investigatory purposes, patted down, searched, and/or arrested. If any of these situations occur, the “stop_type” field would be labeled “Ticket and Non-Ticket Stop.” If an individual is searched, MPD differentiates between person and property searches. The “stop_location_block” field represents the block-level location of the stop and/or a street name. The age of the person being stopped is calculated based on the time between the person’s date ofbirth and the date of the stop.There are certain locations that have a high prevalence of non-ticket stops. These can be attributed to some centralized processing locations. Additionally, there is a time lag for data on some ticket stops as roughly 20 percent of tickets are handwritten. In these instances, the handwritten traffic tickets are delivered by MPD to the DMV, and then entered into data systems by DMV contractors. On August 1, 2021, MPD transitioned to a new version of its current records management system, Mark43 RMS.Due to this transition, the data collection and structures for the period between August 1, 2021 – December 31, 2021 were changed. The list below provides explanatory notes to consider when using this dataset.New fields for data collection resulted in an increase of outliers in stop duration (affecting 0.98% of stops). In order to mitigate the disruption of outliers on any analysis, these values have been set to null as consistent with past practices.Due to changes to the data structure that occurred after August 1, 2021, six attributes pertaining to reasons for searches of property and person are only available for the first seven months of 2021. These attributes are: Individual’s Actions, Information Obtained from Law Enforcement Sources, Information Obtained from Witnesses or Informants, Characteristics of an Armed Individual, Nature of the Alleged Crime, Prior Knowledge. These data structure changes have been updated to include these attributes going forward (as of April 23, 2022).Out of the four attributes for types of property search, warrant property search is only available for the first seven months of 2021. Data structure changes were made to include this type of property search in future datasets.The following chart shows how certain property search fields were aligned prior to and after August 1, 2021. A glossary is also provided following the chart. As of August 2, 2022, these fields have reverted to the original alignment.https://mpdc.dc.gov/sites/default/files/dc/sites/mpdc/publication/attachments/Explanatory%20Notes%202021%20Data.pdfIn October 2022 several fields were added to the dataset to provide additional clarity differentiating NOIs issued to bicycles (including Personal Mobility Devices, aka stand-on scooters), pedestrians, and vehicles as well as stops related specifically to MPD’s Harbor Patrol Unit and stops of an investigative nature where a police report was written. Please refer to the Data Dictionary for field definitions.In March 2023 an indicator was added to the data which reflects stops related to traffic enforcement and/or traffic violations. This indicator will be 1 if a stop originated as a traffic stop (including both stops where only a ticket was issued as well as stops that ultimately resulted in police action such as a search or arrest), involved an arrest for a traffic violation, and/or if the reason for the stop was Response to Crash, Observed Moving Violation, Observed Equipment Violation, or Traffic Violation.Between November 2021 and February 2022 several fields pertaining to items seized during searches of a person were not available for officers to use, leading to the data showing that no objects were seized pursuant to person searches during this time period. Finally, MPD is conducting on-going data audits on all data for thorough and complete information. For Annual Reports and more information regarding police stops, please see: https://mpdc.dc.gov/stopdataFigures are subject to change due to delayed reporting, on-going data quality audits, and data improvement processes.