Cal. Bus. & Prof. Code § 26301

(a) The Governor may enter into an agreement with another state or states authorizing medicinal or adult-use commercial cannabis activity, or both, between entities licensed under the laws of the contracting state and entities operating with a state license, provided that both of the following criteria are met:
1. (1) The commercial cannabis activities are lawful and subject to licensure under the laws of the contracting state.
2. (2) With respect to the interstate transportation of cannabis or cannabis products, the agreement prohibits both of the following:
  1. (A) The transportation of cannabis and cannabis products by any means other than those authorized under both the laws of the contracting state and the regulations of the department.
  2. (B) The transportation of cannabis and cannabis products through the jurisdiction of a state, district, commonwealth, territory, or possession of the United States that does not authorize that transportation.
(b) Notwithstanding any other law, the execution of, and compliance with the terms of, an agreement does not constitute a project for purposes of the California Environmental Quality Act (Division 13 (commencing with Section 21000) of the Public Resources Code).