You are misunderstanding how law works. How a law is enacted does not determine whether it can be overridden. The type of law determines it. So a statute cannot override a constitutional provision. A regulation cannot override a statute. But a statute can override an earlier statute. A law has no special status by being passed by referendum rather than legislature.
As you can see, the proposition altered the Family Code of California, not the state Constitution and could, therefore, be overridden by the legislature. One of the cornerstones of representative democracies (i.e. our republican form of government) is that the legislature is assumed to represent the people and if the people do not like what the legislature passes they vote them out. Passing and then repealing a law is a common thing in any type of democracy.
no subject
The test of Prop 22 is here: http://primary2000.ss.ca.gov/VoterGuide/Propositions/22text.htm
As you can see, the proposition altered the Family Code of California, not the state Constitution and could, therefore, be overridden by the legislature. One of the cornerstones of representative democracies (i.e. our republican form of government) is that the legislature is assumed to represent the people and if the people do not like what the legislature passes they vote them out. Passing and then repealing a law is a common thing in any type of democracy.