The United States and Texas Constitutions give the Legislature specific prioritized criteria in drawing district maps:
- Draw districts with equal population, based on the U.S. Constitution.
- Comply with the federal Voting Rights Act, to ensure minority voters have an equal opportunity to elect candidates of their choice.
- Draw districts that are contiguous, so that a district is connected at all points.
- For State House Districts, county lines may not be crossed if the county holds enough population to contain the district(s).
The overarching intent: One Person, One Vote - districts must be drawn in a manner that neither has the purpose nor will have the effect of denying or abridging the right to vote on the basis of race, color, or language group.
The Texas Legislature also uses partisan data to draw the district lines, taken from election data of both the state's primary and general elections. This allows legislators to choose voters based on party affiliation and how likely they are to vote in an election.