Terms & Definitions

A police department or organization, like "Aurora Police Department". Agencies often have parent-child relationships to one another.
criminal legal system
Law enforcement, courts, and corrections. Our focus is on the United States.
Data Source
A URL pointing to a place on a police website where public records may be scraped, like "". Read more here.
Data Source archive
A raw, unprocessed HTML archive of a Data Source at a specific time.
scraper / data scraper
A bit of code responsible for collecting an Extraction from a Data Source or Archive. Check out the GitHub repo. For more about our philosophy, start here.
Colloquially, "scraper" may refer to a person writing a Scraper.
scraper extraction
The result of running a Scraper is an extraction, usually intended to further parse or process an HTML page or PDF into more usable data.
Packaged with data (like a Data Source or scraper extraction), metadata is information about when and how the data was collected.
data custody / provenance
Who collected and published the data?
agency_described (which agency is the data about?)
originating_entity (who generated the records?)
supplying_entity (who is publishing the records?)
Sometimes these are all the same entity; sometimes they are all different.