About Data for Community Trust

Data for Community Trust (DCT) is an initiative built by AH Datalytics to give residents and community leaders better access to timely, transparent public safety data. Our goal is to strengthen trust between police departments and the communities they serve by making information easier to understand, easier to access, and free for everyone.

DCT takes complex raw data from local systems, like 9-1-1 dispatch, police reports, and traffic stop records, and processes it through a secure pipeline that refreshes every night. The result is a set of clear, interactive dashboards that let residents explore trends in crime, calls for service, and traffic stops over time and in different geographies within the community.

We believe that when data is accessible and transparent, it empowers residents, policymakers, and law enforcement alike. By providing a shared view of what’s happening in the community, DCT helps inform public discussion, support accountability, and guide more effective responses to local needs.

About the Data

Where does the data come from?

Available data supporting this website comes from Hazel Crest’s E-COM 9-1-1 Dispatch Center. This data is collected using Motorola’s Flex Data Exchange Application Programming Interface (API) and processed for the website via the Data for Community Trust Pipeline which runs an Extract, Transform, Load (ETL) process on the raw data to support visualizations on the website. The data pipeline automatically refreshes each night at 12:00AM Central Time (CT) and takes roughly 11 minutes to run.

Data Limitations

Data on this site represents available data that has been digitized by Hazel Crest Police Department. The police department may also keep paper records which are not reflected in the data or visualizations provided on the website.

• Officers and administrators may sometimes go back to records and make updates/ changes. The data included on this site may not include all updates due to the potential lag in digitizing updated records and refreshing
• This website only displays reported crimes, which do not account for all crimes that take place.

Data Privacy

All personal identifiable information (PII) is deidentified during the data extraction process. Locations of domestic, medical, and mental health calls are removed from the data used for the website per the Privacy Principles. All details regarding juveniles involved in any incidents are redacted to obscure sensitive information per the Privacy Principles. Officer information is redacted to obscure identifiable information per the Privacy Principles.

Glossary

Metrics

• YTD (Year-To-Date): Data accumulated from the beginning of the current year up to the most recent reporting date.
• % Change: The percentage difference in crime counts between two time periods, showing increases or decreases.
• Full Year: A running total of all data points (crimes, calls for service, or traffic stops) over the past year from any given day. It smooths out short-term ups and downs (like one unusual week or month) and makes longer-term patterns and seasonal trends easier to see.

Geography

The subdivisions and neighborhoods that make up the Village of Hazel Crest are divided into three zones. Please see the zone breakdown below.

• Zone 1: Hazel Crest Proper
• Zone 2: Twin Creeks, Pottawattamie Hills, Highlands, Appletree, English Valley
• Zone 3: Pace Setter, Stonebridge, Carriage Hills, Chateaux, Stone Creek, Village West, Dynasty Lakes

The following map shows the zone sub-divisions.

Data Types

Crime

Definition: Incidents reported to law enforcement that involve one or more actions considered violations of criminal law.

Crime Types (NIBRS categories):

• Person: Offenses where the victim is an individual, and the crime involves physical harm, threats of harm, or the taking of a person's liberty.
• Property: Offenses involve the unlawful taking, damage, or destruction of property with the primary goal of obtaining money, property, or some other benefit
• Society: Offenses that violate societal norms and prohibitions against certain types of activities. These are typically victimless crimes, where the primary harm is to the public order and morality of society, rather than directly to an individual.

For more information about different crime types and their definitions please refer to the guide to Understanding NIBRS website.

Call for Service

Definition: Requests for police assistance that result in a police response. These can come from residents - such as 911 or non-emergency calls - be initiated by police officers, or be triggered by alarms.

Call Types:
Categories and subcategories were created by AH Datalytics (AHD) to comply with a standardized method that has been used for other jurisdictions across the country. The 7 categories include:

• Miscellaneous Policing: Activities performed by the police that are typically not responding to crimes such as performing maintenance, administrative duties, patrolling, or transporting a prisoner. Administrative incidents are a catchall category that reflects time spent by an officer not serving the public.
• Traffic: These incidents typically involve responding to traffic accidents, enforcing traffic laws (other than DUI), and directing traffic.
• Service: Incidents that involve responding to community issues that are typically non-criminal such as answering a burglar alarm, taking a report on a missing person, or chasing an escaped or loose animal.
• NIBRS Property: Defined by the FBI as auto theft, burglary, and theft. This does not include theft by fraud, forgery, or embezzlement.
• NIBRS Society: Defined by the FBI as crimes that “represent society’s prohibition against engaging in certain types of activity (for example liquor law violations or narcotics offenses); they are typically victimless crimes in which property is not the object.”
• Other Crimes: Incidents that are criminal in nature but do not fit in FBI’s Uniform Crime Report (UCR) Part I categories (criminal homicide, rape, robbery, aggavated assault, theft, auto theft, and burglary). These range from city ordinance violations to kidnapping.
• NIBRS Person: Defined by the FBI as criminal homicide, rape, robbery, and assault.

Call Priority Levels:

• Emergency: Calls labeled as priority 0 or 1 in the data. Events that are in progress where persons or high-value property are in immediate danger. Requires a multiple unit response or multiple groups of officers.
• Non-Emergency: Calls labeled as 2-9 in the data. Events that are in progress where persons or high-value property are in immediate danger. Requires a multiple unit response or multiple groups of officers.

Response Times:
Response time is how long it takes an officer to arrive at a call for service. It is measured in minutes, calculated as the difference between when a call is received or dispatched and when the first officer arrives on scene. Some calls are excluded from calculations due to data error or omission; these include arrival times less than 0 minutes, greater than or equal to 720 minutes, officer-initiated/reported calls, and calls opened in error.

• Average response time: The arithmetic mean of all calls for service response times, calculated by adding all response times and dividing by the number of calls.
• Median response time: The middle value of all calls for service response times when ordered from fastest to slowest, showing the point at which half of calls are faster and half are slower.
• 90th percentile response time: The response time under which 90% of all calls for service are answered, meaning only 10% take longer. This is useful for conveying the longest individuals might expect to wait.

Traffic Stops

Definition: When a police officer temporarily detains a driver and their passengers — commonly known as being “pulled over” - to investigate a traffic violation or potential crime.