From the Competitive Enterprise Institute:

Furthermore, even when the safety assessment letter template and review process are established, they are likely to remain voluntary for at least some period of time. Until NHTSA formally establishes regulations standardizing and requiring the submission of the safety assessment letter through the notice-and-comment rulemaking process, it is inappropriate for states to attempt to mandate that developers comply with nonbinding federal guidance—an edict which is itself in direct contradiction of the FAVP guidance. For this reason, the California DMV should remove all references to the safety assessment letter from its final testing and deployment rules.

Ian Adams at the R Street Institute discusses some more elements of the proposed California rules here.

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