Erwin Chermerinsky, Dean of the U.C. Berkeley School of Law, has this op-ed in the Los Angeles Times, saying that the new California law requiring presidential primary candidates to reveal their tax returns is constitutional.
The op-ed does not mention the California Constitution, which tells the Secretary of State to put all “recognized” candidates for a party nomination on one of the presidential primary ballots.
The op-ed says the law does not violate the U.S. Constitution because any presidential candidate is free to reveal his or her tax returns. However, that ignores court decisions which have struck down other requirements for ballot listing (for federal candidates) that were voluntary. The 10th circuit decision Campbell v Davidson, 233 F.3d 1229 (2000) said Colorado could not keep a congressional candidate off the ballot just because he refused to register to vote. He was entirely free to register; he was a resident of Colorado.
The highest state court in Maryland, the Court of Appeals, ruled in 1950 in Shub v Simpson, 76 A. 2d 332, that Maryland could not keep a congressional candidate off the ballot because she refused to sign a loyalty oath.
The Minnesota Supreme Court ruled in Backstrom v Kiffmeyer, A04-1647, in 2004, that Minnesota could not keep a congressional candidate off the Republican primary ballot on the grounds that the candidate lived in Rome, Italy. He was free to come home to Minnesota, but he chose not to.
The Ninth Circuit ruled in Schaefer v Townsend, 215 F.3d 1031 (2000) that California could not keep a congressional candidate off the ballot on the grounds that he wasn’t registered to vote in California. He had homes in both California and Nevada, but chose to be registered in Nevada. He could have changed his registration to California, but chose not to.