A "modified closed primary" was in effect in California from 2001 to 2011. Each political party could decide whether or not they wish to allow unaffiliated voters to vote in their party's primary. This appeared to avoid the constitutional concerns of both the open and the closed primary. In the 2004 and 2006 primary elections, the Republican, Democratic, and American Independent parties all opted to allow unaffiliated voters to request their party's ballot. However, since the 2008 presidential primary election, only the Democratic and American Independent parties have taken this option, while the Republican party has not.