The Attorney General of Guam says a law change will not help the governor's case to borrow more than 240-million US dollars on the bond market.
Governor Felix Camacho signed a new law this week following the Attorney-General's refusal to approve the bond bill.
The law clarifies a tax definition which determines how much money the financially-troubled government can borrow.
The new definition means the government could borrow the full appraised value of land in Guam.
But the attorney-general, Douglas Moylan, says he will not sign off the bond bill yet.
"Our office still has a problem because we don't know what the appraised value of property is because they haven't done it since 1993. What's happened is our Revenue and Taxation Department has been extrapolating values for the last ten years"
Mr Moylan says an appraisal needs to be done - otherwise the government will be borrowing against an unreal figure.
The governor is expected to take his case to the Supreme Court next week.