ST. PAUL — A series of disclosures about Gov. Sarah Palin, Senator John McCain’s choice as running mate, called into question on Monday how thoroughly Mr. McCain had examined her background before putting her on the Republican presidential ticket.

Among other less attention-grabbing news of the day: it was learned that Ms. Palin now has a private lawyer in a legislative ethics investigation in Alaska into whether she abused her power in dismissing the state’s public safety commissioner; that she was a member for two years in the 1990 of the Alaska Independence Party, which has at times sought a vote on whether the state should secede; and that Mr. Palin was arrested 22 years ago on a drunken-driving charge.