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Overview: Proposed Colorado State Legislative Redistricting Reform Amendment (Amendment Z)

An overview of a proposed constitutional amendment to create a state legislative redistricting commission in Colorado.

Published: October 12, 2018

The Colorado legislature unanimously approved a constitutional amendment that, if approved by voters, would create a twelve-member redistricting commission to draw state legislative lines beginning in 2021. The amendment will go before voters this November. A copy of the proposed amendment can be found here

Key Features

What Maps the Commission Will Draw

State legislative districts

Commission Size

Twelve members (4 Democrats, 4 Republicans, 4 unaffiliated)

Who is Eligible to Be a Commissioner

All members of the commission must be registered voters who voted in the previous two general elections. Commissioners must have been affiliated with the same political party or unaffiliated with any political party for a minimum of five consecutive years prior to their appointment.

Commissioners may not have been candidates for the general assembly within the last five years and may not serve on Colorado’s congressional redistricting commission (the subject of Amendment Y, also being voted on this November). In addition, commissioners may not have been, within the last three years:

• Compensated by a member of the general assembly or a campaign committee advocating for the election of a candidate to the general assembly;

• Elected public officials at the federal, state, county, or municipal level;

• Elected political party officials above precinct level or employees of a political party; or

• Professional lobbyists registered at the federal, state, or municipal level.

How Commissioners are Selected

Those interested in serving on the commission must submit an application using a form provided by the staff of the Colorado General Assembly’s Legislative Council and the Office of Legislative Legal Services.

The form will be made available to the public on the Colorado legislature’s website, or through a comparable means, and will ask applicants to provide information about their professional background, party affiliation, past political activity, and a list of all political and civic organizations the applicant has belonged to in the last five years. Applicants must also explain why they want to serve on the commission and how they will promote consensus among commissioners if appointed. Applicants may choose to submit up to four letters of recommendation.

Once the applications have been submitted, nonpartisan staff and the secretary of state will review applications to determine applicants’ objective qualifications to serve on the commission. These findings will be made public.  

Qualified applications will then be reviewed by a panel of three recently retired Colorado Supreme Court justices and/or Colorado Court of Appeals judges who are not of the same political party. If there are fewer than three eligible participants for the panel, the chief justice of the Colorado Supreme Court will appoint the most recently retired district court judge who has not been affiliated with the same political party as any previous appointee to the panel. Members of this panel may not serve on the corresponding panel to choose congressional redistricting commissioners. Decisions on selection of potential commission members require unanimous approval from all three members of the panel.

The following process then will be used to select commissioners:

1. From qualified applicants, the judicial panel will randomly select 300 applicants from the state’s largest political party, 300 applicants from the state’s second largest political party, and 450 applicants unaffiliated with any political party. If there are fewer applicants than the pool size, all applicants will be included in the pool.

2. The panel will then hold one or more public hearings, after which it will select 50 people from each initial pool who best demonstrate experience in representing the interests of groups or associations in Colorado, relevant analytical skills, ability to be impartial, and ability to promote consensus on the commission.

3. The panel will then choose six commissioners by lot, drawing two applicants from each of the three final pools (i.e., 2 Democrats, 2 Republicans, and 2 unaffiliated). No then-existing congressional district may be represented by more than one commissioner until each of Colorado’s congressional districts has been represented, and no congressional district can be represented by more than two commissioners.

4. After the initial six commissioners are appointed, the four legislative majority and minority leaders in the Colorado legislature will each select ten qualified applicants affiliated with one of the state’s two largest political parties from the initial pool of applicants and notify the judicial panel of their selections.

5. The panel will then select one commissioner from each of the legislative leaders’ pool of applicants. In addition, the panel will pick two unaffiliated commissioners from the pool of 450 randomly- drawn unaffiliated applicants. As a part of this selection process, the panel can choose to interview applicants before making its appointments. While selecting commissioners, the judicial panel must ensure that the commission, to the extent possible, reflects the state’s racial, ethnic, gender, and geographic diversity, that at least one but no more than two commissioners come from any single congressional district, and that at least one commissioner resides west of the Continental Divide.

How a Map Gets Approved

Eight of 12 members of the commission, including at least one unaffiliated member, must vote for a plan in order for it to be approved.

Preliminary Plan and Public Hearings. The commission’s nonpartisan staff will prepare and publish a preliminary plan between thirty and forty-five days after the commission has convened or the necessary census data is available, whichever is later. The commission then must hold public hearings around the state on the preliminary plan. These hearings must be completed by July 21, 2021.

Subsequent Plans. Following the public hearings on the preliminary plan, the nonpartisan staff will draft up to three plans for the commission. Commissioners may request additional maps during public hearings. The commission can also provide direction for the development of the staff plans with a consensus of eight commissioners, one of whom must be unaffiliated. The drafting process ends once the commission votes to adopt a plan, which can happen at any time after the presentation of the first staff plan. All plans will be published online.

Voting on a Plan. The commission cannot vote on a plan until at least 72 hours after the plan has been proposed in a public meeting or was last amended, but this requirement can be waived by unanimous vote. The commission must submit the adopted plan for the Colorado Supreme Court to review and may grant its staff the authority to make technical de minimis adjustments to the adopted plan before doing so.

The commission must adopt a final plan by September 15, 2021. If the commission fails to do so by the deadline, the nonpartisan staff will submit the third staff plan to the Colorado Supreme Court as the final plan.

The Colorado Supreme Court will review the final plan and determine whether it complies with the criteria. If the court rules that the plan is defective, the commission will have twelve days to hold a public hearing and return an amended plan. If the commission fails to submit a plan within twelve days, the commission’s staff will have three additional days to submit a revised plan. 

The Colorado Supreme Court must approve a plan no later than December 29, 2021.

The Rules That Must Be Followed in Drawing a Map

Basic Criteria. The state legislative plan must:

1. Make a good-faith effort to achieve precise mathematical population equality between districts, with no more than a five percent deviation between the most and least populous districts. Districts must consist of contiguous geographic areas;

2. Comply with the Voting Rights Act;

3. Preserve whole communities of interest and whole political subdivisions such as counties, cities, and towns;

4. Ensure districts are as compact as reasonably possible; and
5. Maximize the number of politically-competitive districts after adhering to the required criteria and considering the above factors.

Anti-Gerrymandering Provision. A plan may not be drawn for the purpose of protecting incumbent members, candidates, or any political party.

Protections for Communities of Color. A plan also may not be drawn for the purpose of or have the effect of denying or abridging the right of any citizen to vote or diluting the impact of a racial or language minority group’s electoral influence.

Requirement of a Report. When a final plan is approved and submitted, the staff will publish a report demonstrating how the plan reflects the evidence and findings concerning the extent to which competitiveness is fostered and is consistent with the criteria.

Public Input and Transparency

Public engagement is required during both the commissioner selection process and the map development process.

Commissioner applications will be public records and must be posted on the Colorado legislature’s website. Nonpartisan staff must make public their findings and reasoning about the objective qualification of all applicants. The judicial panel must hold at least one public hearing in between the first and second rounds of selection of applicants.

The commission must create and maintain a website or a comparable means of communicating with the public. Colorado residents can present proposed maps or make written comments for the commission’s consideration. All written comments must be published on the commission’s website.

The commission must also provide opportunities for residents to present testimony at public hearings. Public hearings must be attended by at least ten commissioners, in person or electronically, and must be broadcast and archived on the internet. The commission must hold public hearings on the preliminary plan in multiple areas across the state.

The commission may not approve a final plan until the commission holds at least three hearings in each congressional district, including at least one in a location west of the continental divide, one hearing east of the continental divide, and either one hearing south of El Paso County’s Southern Boundary or east of Arapahoe County’s Eastern Boundary.

The commissioners are subject to state statutes regarding open meetings, and, along with the staff, are subject to open records provisions. The commission’s staff may not communicate about any plan outside of public hearings with anyone except other staff members. The staff must report any attempts to exert influence over drafting redistricting plans to the commission. Commissioners may not communicate with their staff about mapping districts outside of a public meeting or hearing, with the exception of designated staff who may communicate with the commissioners regarding administrative matters defined by the commission.

Any person who contracts for or receives compensation for advocating to the commission or to the staff must disclose their compensation details and the person or entity paying for their services to the secretary of state. The secretary of state must publish the names of these lobbyists, the compensation they received, and the persons for whom they work on the secretary’s website.

Timing for the Next Round of Redistricting 

  • August 10, 2020: Commissioner application period opens.
  • November 10, 2020: Deadline for application submissions.
  • By January 5, 2021: The chief justice of the Colorado Supreme Court selects a panel of justices or judges to review applications.
  • By January 11, 2021: The legislative staff notifies applicants of their eligibility to serve on the commission.
  • By January 25, 2021: The judicial panel draws the first round of random selection of applicants in a public meeting.
  • By February 15, 2021: The judicial panel concludes public hearings, selects pool of 150 qualified applicants, and appoints six applicants to the commission.
  • By February 16, 2021:  The legislative leaders notify the judicial panel of their selections for the commission.
  • By March 16, 2021: The judicial panel selects one commissioner from each legislative leader’s pool of applicants and two commissioners unaffiliated with any political party.
  • By March 30, 2021: The governor convenes the commission.
  • By July 21, 2021: The commission completes public hearings on the preliminary plan.
  • By September 15, 2021: The commission adopts a final plan.
  • By November 15, 2021: The Colorado Supreme Court approves the plan or returns the plan to the commission.
  • By December 29, 2021: The Colorado Supreme Court approves a revised plan.

Terms of Office

Individuals serve on the commission until the next redistricting cycle.


The Colorado legislature must appropriate sufficient funds for the compensation and expenses of the commission, the commission’s staff, and the judicial panel. Commissioners will receive a per diem allowance and reimbursement for reasonable expenses.

A PDF of the full text of Amendment Z can be found here. A PDF version of this analysis can be found here.

This proposal overview is informational and does not imply endorsement by the Brennan Center for Justice.