[JURIST] The ACLU of Michigan [advocacy website] filed a federal suit Friday challenging a Michigan election law that limits access to information on presidential primary voters to the Democratic and Republican parties. The complaint [text, PDF] alleges that Section 615c [text] of the Michigan Election Law [text] is unconstitutional because it excludes other smaller parties, as well as individuals, citizen groups and news media, from seeing lists of voter preferences and gives preference only to the two major parties in violation of the Equal Protection Clause and 14th Amendment [Cornell Law backgrounders]. The ACLU said [press release]:

Michigan law does not require voters to register by party and therefore voter party preference information is valuable to political parties, individual candidates, citizen groups supporting or opposing ballot proposals, political consultants, news media, researchers, other specialized groups and members of the public.