The U.S. Supreme court will decide whether President Obama's healthcare reform is constitutional on Thursday. Republicans have been criticising the bill. The law is closely modeled on Massachussets reform, which Mitt Romney, a Republican himself, helped desiging when he was governor there. It is the only state that requires all its legal residents to be medically insured, whether paid for by employers, workers or the government. Those who refuse to carry coverage pay a penalty -- an average $1,200 a year. As for Romney, a presumtive nominee for the next US presidential elections, he still defends the state law, yet insists that it should not be forced on the rest of the country. Al Jazeera's Tom Ackerman reports from Boston.