California Senate Bill 420

California Senate Bill 420 (colloquially known as the Medical Marijuana Program Act) was a bill introduced by John Vasconcellos of the California State Senate, and subsequently passed by the California State Legislature and signed by Governor Gray Davis in 2003 "pursuant to the powers reserved to the State of California and its people under the Tenth Amendment to the United States Constitution." It clarified the scope and application of California Proposition 215, also known as the Compassionate Use Act of 1996, and established the California medical marijuana program. The bill's title is notable because "420" is a common phrase used in cannabis culture.

The bill specifically:

In enacting the bill it was the intent of the legislature to:

The bill reflects a compromise between patients' advocates and law enforcement. It also required counties to implement a voluntary patient identification card system and other provisions to protect patients and their caregivers from arrest. The guidelines were hotly disputed by California NORML and other patients' advocates. Patient advocates had pushed for more liberal guidelines, such as those adopted by Sonoma County, which allow up to 30 plants in a 100-square-foot (9.3 m²) growing area plus 3 pounds of marijuana. The final guidelines were decided in a last-minute legislative deal by Attorney General Lockyer and Sen. Vasconcellos in order to get the bill passed.

In recognition of the fact that the guidelines are inadequate for many very ill patients, SB 420 allows patients to be exempted from them if they obtain a physician’s statement that they need more. In deference to local autonomy, SB 420 also allows counties and cities to establish higher - but not lower - guidelines if they so choose. As a result, the new law will not overturn liberal guidelines that are now in effect in Sonoma and elsewhere. However, it should force more restrictive counties, such as San Bernardino and Fresno, which have heretofore had "zero tolerance" policies, to honor the new statewide minimum standard. Many counties have increased the limits of possession and cultivation since the passage of the law in 2003. It also specifically allowed cannabis cooperatives.

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