Alaska Republicans are asking the state's highest court to block an abuse-of-power investigation into vice presidential nominee Sarah Palin's firing of a state commissioner before a potentially embrassing report on the matter is released.

Five GOP state lawmakers, in a brief filed Monday, say the inquiry has exceeded its authority and is too political.

Palin is the focus of a legislative investigation into allegations she abused her power by firing her public safety commissioner. The commissioner says he was pressured to dismiss a state trooper who was involved in a messy divorce with Palin's sister.

Investigators are scheduled to submit a report on the investigation Friday. Oral arguments are scheduled for Wednesday.