Mrs Palin will also be interviewed as part of the probe
Todd Palin, husband of Republican vice-presidential nominee Sarah Palin, has been ordered to testify to an inquiry into her alleged abuse of power.
The Alaska legislative probe began after Mrs Palin was accused of pressuring staff to fire her sister's ex-husband as a state trooper.
Mrs Palin, the governor of Alaska, denies any improper behaviour.
Twelve other witnesses will also be required to give evidence, although Mrs Palin will not receive a subpoena.
Officials say she will be interviewed as part of the investigation, however.
The probe into the affair - referred to by some as "Troopergate" - began before Republican presidential nominee John McCain picked Mrs Palin as his running mate.
In July, the Alaska state legislature appointed retired prosecutor Stephen Branchflower to look into allegations that Mrs Palin had removed Alaska's Public Safety Commissioner Walt Monegan after he had refused her request to fire her ex-brother-in-law, Mike Wooten.
Critics said Mrs Palin was using her power as governor to pursue a personal feud.
Mr Branchflower is also investigating whether a Palin administration official, Frank Bailey, improperly accessed Mr Wooten's personnel file.
Concerns were raised when a recording emerged of Mr Bailey discussing confidential information about Mr Wooten with an Alaska State Trooper lieutenant.
Mrs Palin insists that she fired Mr Monegan over disagreements about budget priorities, while Mr Bailey says he learned of Mr Wooten's personal details from Todd Palin, not from Mr Wooten's file.