By Dan Walters | CalMatters Columnist

Four months out from November’s election — and just three months until mail voting begins — outcomes of virtually all major California races are preordained, including a win by the presumptive Democratic presidential nominee, Joe Biden.

The big action will be 12 statewide ballot measures that may differ widely in subject matter, but have a common theme: do-over.

All but two of the measures would re-fight old battles, including the proposals most likely to grab the spotlight, Propositions 15 and 16.

The former is a clash that’s been brewing since 1978, when voters passed Proposition 13, California’s iconic property tax limit.

Public employee unions want to undo Proposition 13 and their initial effort is Proposition 15, removing some taxation limits from commercial properties such as office buildings and shopping centers. It would raise as much as $12.5 billion a year and with those high stakes, $100-plus million likely will be spent by proponents and opponents in the commercial real estate industry.

Proposition 16, placed on the ballot by Democratic legislators, would repeal Proposition 209, a 1996 measure that banned the use of race, ethnicity or gender in governmental actions, including college admissions. The debate over “affirmative action” has gathered new energy with the Black Lives Matter and other protests about racial disparities.

Proposition 19, a legislative version of a previously unsuccessful measure backed by the California Association of Realtors, also revisits Proposition 13 by allowing homeowners over 55 to buy new homes and transfer taxable values of their old homes to the new ones.

Another big do-over, sponsored by law enforcement groups, would change parts of two previous ballot measures (Propositions 47 and 57) that eased up on criminal penalties. Proposition 20’s backers say 47 and 57 freed too many criminals who commit new crimes.

Proposition 25 is another criminal justice measure in the midst of a fierce debate over cops’ treatment of non-white Americans and another do-over. Backed by bail bond agents, the referendum would repeal the Legislature’s landmark elimination of cash bail, which reformers said discriminates against poor defendants.

Proposition 22 is also an effort to undo a legislative decision, in this case, Assembly Bill 5, which cracked down on employers who used non-payroll workers, such as ride-hailing services Uber and Lyft. They and their allies want to exempt themselves from AB 5’s provisions, but face stiff opposition from labor unions.

Two years ago, Los Angeles housing activist Michael Weinstein couldn’t persuade voters to eliminate curbs on local rent control ordinances and he’s back this year with Proposition 21, a somewhat softer version, but still opposed by landlords.

Proposition 23 is another revival of a measure rejected by voters. Backed by a healthcare union, it would impose staffing levels and other operational rules on clinics that provide dialysis care to those with defective kidneys.

Two years ago, privacy advocates dropped a ballot measure aimed at protecting Californians’ personal data in favor of legislation, but they dislike the results and have a new proposal, Proposition 24, that would go further.

Sixteen years ago, California voters approved a $3 billion state bond issue for stem cell research. The money has all been spent and researchers drafted Proposition 14, a $5.5 billion bond for the California Institute for Regenerative Medicine.

Those are the 10 do-overs. The remaining two measures, Propositions 17 and 18 would change state voting rules, allowing felons to cast ballots and allowing 17-year-olds to vote in primary elections if they would turn 18 by the November election.

Let the battles of information and misinformation begin.

CalMatters is a public interest journalism venture committed to explaining how California’s state Capitol works and why it matters.

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