Thanks everyone for providing some answers. The statement they claim that they live Florida so that they don't have to pay Florida state income taxes was suppose to say they claim that they live in Florida so that they don't have to pay Michigan State income taxes. The reason that the husband changed his drivers license and legal address to Florida, car license plates and voters card (and also claims to live in Florida for183 days is to prove his Florida residency. However, my sister still has a Michigan driver's license, votes in Michigan.
The question remains if they claim their Michigan house as their homestead exemption, live in Florida for 183 days and each have different state residency's shouldn't they at least have to file Michigan state income taxes? Or file seperately rather than married filing jointly?
