Understanding the Data

Open States data adheres to a schema that has evolved over our 11+ years of working with legislative data. Our goal is to provide as much uniformity across states as possible while still allowing for the wide diversity of legislative processes between the states.

These docs both catalog the schema and attempt to explain some of those choices, particularly where they might be surprising.

Main Concepts

The main concepts are defined below. You'll notice these concepts mostly correspond to the v2 GraphQL root nodes.

Concept	Definition
Jurisdiction	Essentially just another word for "State" in our context. (Includes DC and Puerto Rico.)
Session	A period of time in a legislature where the same members serve together, typically punctuated by elections. All bills in a session will be uniquely numbered. (e.g. HB 1 in the 2017 session is typically not the same bill as in the 2019 session)
Bill	Represents all types of legislation whether it is a bill, resolution, etc.
Vote	A vote among members of the legislature, typically an entire chamber but can also be a committee vote.
Person	Any person that is associated with the legislature.
Organization	A generic term used to represent a few different concepts: legislatures, chambers, committees, and political parties.
Post	A particular role within an organization, typically used to represent a seat in the legislature. (e.g. the District 4 post in the North Carolina Senate Organization)
Membership	Ties a Person to a Post for a duration of time.