ANCHORAGE, Alaska – An investigator hired by Alaskan lawmakers to probe abuse-of-power allegations against Gov. Sarah Palin was free to finish his work by a deadline set for a week from Friday after a state judge dismissed a lawsuit seeking to block the probe.

The investigation is looking into whether Palin, the Republican vice presidential nominee, and others pressured Public Safety Commissioner Walt Monegan to fire a state trooper who was involved in a contentious divorce from Palin's sister, and then fired Monegan when he wouldn't dismiss the trooper. Palin says Monegan was ousted over budget disagreements.

Judge Peter Michalski on Thursday threw out the lawsuit filed by five Republican state legislators who claimed the investigation had been manipulated by Palin enemies who wanted to produce a damaging report just weeks before Election Day. Their attorney, Kevin Clarkson, said the legislative body that ordered the investigation had exceeded its authority.

But Michalski agreed with defense attorney Peter Maassen, who argued that the Legislature has broad authority to investigate the governor. The mere appearance of impropriety does not mean any individual's right to fairness was violated, Michalski wrote in his decision.

“It is legitimately within the scope of the legislature's investigatory power to inquire into the circumstances surrounding the termination (of) a public officer the legislature had previously confirmed,” the judge wrote.

The independent investigator, retired prosecutor Steven Branchflower, now can conclude the probe and report his findings by Oct. 10. Branchflower has not interviewed Palin's husband Todd and several top aides who have refused to appear under subpoena. It was not immediately clear whether they now would testify.

“It's free to continue,” said Maassen, who represented the Legislative Council, 10 Republicans and four Democrats who authorized the investigation, and others involved in the probe.

Clarkson said in a statement that the judge's decision was “dangerous because it robs every Alaskan of the protection specifically provided by the Alaska Constitution” for due process.

At first, Palin agreed to cooperate with the probe, but since being picked Aug. 29 to be Sen. John McCain's running mate, she, her family and staff have instead said the legislative investigation has been compromised by politics and that they would cooperate only with a separate investigation run by the Alaska State Personnel Board, whose members Palin can fire.

Michalski also threw out a lawsuit filed by Palin aides seeking to dismiss subpoenas compelling their testimony in the investigation. The aides had argued that the subpoenas should not have to be honored because they should not have been issued.

Todd Palin also refused to testify under subpoena, but he was not a plaintiff in the lawsuit filed by the state. His attorney, Thomas Van Flein, declined to say whether Palin would now testify, saying he had not seen the ruling to study the options.

“The question was never if Mr. Palin would testify, only where. The personnel board or the committee,” Van Flein said by e-mail. “Now it could be both. But no decision has been made.”