California Gaming Tribes Preparing For Sports Betting Push In 2028

Summary

Tribal leaders in California, led by James Siva of the California Nations Indian Gaming Association (CNIGA), are preparing a ballot initiative to legalise both in-person and online sports betting in 2028. The announcement came during the Indian Gaming Association’s annual conference, with Siva saying tribes have been meeting behind closed doors and are now willing to speak publicly about plans.

The push is partly a response to the rise of prediction markets (such as Kalshi and Polymarket) and sportsbook-run prediction products, which tribes say siphon revenue without adding local jobs. Tribes are litigating against Kalshi in California and plan a study to quantify revenue loss from these platforms.

The move follows the bitter 2022 fights over Propositions 26 and 27 — costly campaigns in which tribes and commercial sportsbooks spent hundreds of millions of dollars and both measures failed decisively. Polling since then has shown majority support among registered voters for legal sports betting, and the tribal effort signals another major statewide campaign ahead of 2028.

Key Points

CNIGA is preparing an initiative to put retail and online sports betting on California’s 2028 ballot.
James Siva said tribes have been working privately and are now discussing plans publicly.
Prediction markets (Kalshi, Polymarket) and sportsbook-operated markets are a key driver of the new push; tribes claim material revenue loss.
Several tribes are pursuing litigation against Kalshi after a 2025 court decision denied an injunction.
The 2022 ballot fights (Props 26 and 27) were extremely expensive and both measures were rejected by voters.
Legal online sports betting in California requires a constitutional amendment and a statewide vote — a high hurdle for any campaign.
Polling shows increased public support (around 60% in a recent survey), which may encourage a renewed tribal effort in 2028.
State regulators and officials have also moved on related unregulated gambling issues, including DFS and sweepstakes casino rulings and bans.

Context and relevance

California represents the largest untapped regulated sports-betting market in the US; any successful tribal-backed ballot measure would reshape the national industry. The tribes’ renewed effort comes amid expanding prediction markets and changing regulatory stances in the state, creating both competitive and legal pressure on existing operators.

For operators, regulators and investors, this story matters because a tribal-led 2028 initiative could reconfigure market access, partnership models and revenue flows in one of the country’s most lucrative jurisdictions. It also highlights how new products (prediction markets) can accelerate political responses from incumbent stakeholders.

Why should I read this

Short answer: because if you care about where the US sports-betting industry is heading, California is the big-ticket item. Tribes are gearing up for a major 2028 push after losing the 2022 fight — and prediction markets have added urgency. This piece saves you time by boiling down the politics, legal drama and what it could mean for operators and regulators.