California Constitution, Article I, Section 9:
A bill of attainder, ex post facto law, or law impairing the obligation of contracts may not be passed.
OMG! Now California wants to tax text-messaging?
https://www.mercurynews.com/2018/12/...ext-messaging/
State regulators have been ginning up a scheme to charge a fee for text messaging on mobile phones to help support programs that make phone service accessible to the poor. The wireless industry and business groups have been working to defeat the proposal, now scheduled for a vote next month by the California Public Utilities Commission.
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But they add that under the regulators’ proposal the charge could be applied retroactively for five years — which they call “an alarming precedent” — and could amount to a bill of more than $220 million for California consumers.