California Code, Penal Code - PEN § 13655

(a) A department or agency that employs peace officers shall not authorize or allow its employees to wear a uniform that is substantially similar to any uniform of the United States Armed Forces or state active militia.

(b) A department or agency that employs peace officers shall not authorize or allow its employees to wear a uniform that is made from a camouflage printed or patterned material.

(c) For purposes of subdivision (a), a uniform is “substantially similar” if it so resembles an official uniform of the United States Armed Forces or state active militia as to cause an ordinary reasonable person to believe that the person wearing the uniform is a member of the United States Armed Forces or state active militia.  A uniform shall not be deemed to be substantially similar to a uniform of the United States Armed Forces or state active militia if it includes at least two of the following three components:  a badge or star or facsimile thereof mounted on the chest area, a patch on one or both sleeves displaying the insignia of the employing agency or entity, and the word “Police” or “Sheriff” prominently displayed across the back or chest area of the uniform.

(d) This section applies to personnel who are assigned to uniformed patrol, uniformed crime suppression, or uniformed duty at an event or disturbance, including any personnel that respond to assist at a protest, demonstration, or similar disturbance.  It does not apply to members of a Special Weapons and Tactics (SWAT) team, sniper team, or tactical team engaged in a tactical response or operation.

(e) This section does not apply to the Department of Fish and Wildlife.