"Bi-coastal Tax Chutzpah: CA & NY Congressmen Say They Live in Maryland to Claim Property Tax Break on Million Dollar Vacation Homes":

Prof. Paul Caron at TaxProf Blog blogs about this, and links to various news stories. I don't know tax law well enough to have an informed opinion, but Caron does know tax law, and seems to think there is indeed some misbehavior there.