California state law. This says wage taxes are allowed, but not income taxes:<p><a href="http:&#x2F;&#x2F;taxes.about.com&#x2F;od&#x2F;statetaxes&#x2F;a&#x2F;States-Prohibiting-City-Income-Taxes.htm" rel="nofollow">http:&#x2F;&#x2F;taxes.about.com&#x2F;od&#x2F;statetaxes&#x2F;a&#x2F;States-Prohibiting-Ci...</a><p>Not sure how that would specifically play out, but employers are probably better at manipulating cities than residents.