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Headshot of Diane Papan

Diane Papan

Democrat, State Assembly
District 21, San Mateo
Time in office:
  • Assembly: 2022-present

News coverage of Diane Papan

Bio

Diane Papan’s family name has deep ties to the Assembly, though Papan herself is a relative newcomer. Her father, Lou Papan, was known as the “Dean of the Assembly” for the two decades he spent in the chamber. Papan earned a political science degree from UCLA and a law degree from the UC Hastings College of Law. Papan, 62, worked as an attorney and was mayor and city councilmember for the city of San Mateo. She chairs the Assembly Committee on Water, Parks, and Wildlife. She and her husband have one daughter.

Leader Badges

Environment Badge

Ideology

Left

Moderate

Right

Bill Activity

0

Of 36 bills:
5 Passed
9 Failed
22 Pending

For this session year, this legislator initiated 36 bills: 5 passed, 9 failed, and 22 are currently pending.

Alignment Meter

See all-time percentage of this legislator’s alignment with any organization based on total votes.

xx%votes: xx

Influence

There are three categories of donations to legislators after they are elected that encourage a working relationship between the donor and the legislator. The three categories are: 1-Gifts, 2-Travel, 3-Behests.

Giver
Value
Date
Description
Women in CA Leadership$46Dec 5, 2022plant/pin
Senator Bill Dodd$45Dec 6, 2022gift basket

Gifts

Legislators are not allowed to accept gifts of more than $10 per month from registered lobbyists. Gifts from any other single source are limited to $590 in a calendar year.

Gift Received Rating
#102/120

This legislator is ranked 102nd highest for the amount of personal gifts received.

Policy

Bills Authored by Diane Papan

AB 2469
Data centers: water use disclosures.

Committee: Assembly Standing Committee on Water, Parks, and Wildlife

In Progress
Data centers: water use disclosures.Committee: Assembly Standing Committee on Water, Parks, and Wildlife
AB 1931
Insurance: home protection companies.

Committee: Assembly Standing Committee on Insurance

In Progress
Insurance: home protection companies.Committee: Assembly Standing Committee on Insurance
ACR 219
California OB-GYN Week.

Committee: Assembly Standing Committee on Rules

Passed
California OB-GYN Week.Committee: Assembly Standing Committee on Rules
View All Bills

Committees

Most of the policy work in the state Capitol is done in “Standing” committees. Legislators also work on budget subcommittees. There are also “Special” and “Select” committees with a more narrow topic focus. And there are “Joint” committees with members from the Senate and Assembly.

Hearings

Featured Comments

Below are links to the video and transcript of recent, substantive comments by this legislator in committee hearings or floor sessions.

Preview image for AB 261914MIN
Jul 1, 2026

AB 2619

Water resources: data centers.

Preview image for AB 246926MIN
Jul 1, 2026

AB 2469

Data centers: water use disclosures.

Preview image for AB 23226MIN
Jul 1, 2026

AB 2322

Water discharge: commercial, industrial, or institutional sites.

Preview image for AB 223412MIN
Jul 1, 2026

AB 2234

California Environmental Quality Act: geothermal exploratory projects: geothermal technology pilot projects: Geologic...

Preview image for AB 238010MIN
Jun 30, 2026

AB 2380

Pest control: registration fees.

Preview image for AB 17725MIN
Jun 30, 2026

AB 1772

Fish and wildlife: invasive species: invasive mussels.

Preview image for AB 229610MIN
Jun 24, 2026

AB 2296

Planning and zoning: housing element: regional housing needs allocation.

Preview image for AB 19317MIN
Jun 24, 2026

AB 1931

Insurance: home protection companies.

Preview image for AB 22349MIN
Jun 24, 2026

AB 2234

California Environmental Quality Act: geothermal exploratory projects: geothermal technology pilot projects: Geologic...

Preview image for AB 246928MIN
Jun 23, 2026

AB 2469

Data centers: water use disclosures.

Preview image for AB 177223MIN
Jun 23, 2026

AB 1772

Fish and wildlife: invasive species: invasive mussels.

Preview image for AB 24699MIN
Jun 23, 2026

AB 2469

Data centers: water use disclosures.

View All Hearings

District

View of map with yellow overlay for Assembly District 21 boundaries.
District 21 is a Safe Democratic District
Democratic Party candidate has a very high likelihood of winning in an election

Previous Election (2024):

Diane Papan
73.8%
WON
Mark Gilham
26.2%

Party Registration

Census Data

Median age0102030

Median age