Wade Davies, attorney for David C. Kernell, is questioning a magistrate's authority to issue search warrants for Internet companies outside Tennessee.
The magistrate, Clifford Shirley, allowed Davies on Wednesday to pursue his challenge despite a looming April 20 trial date.
Kernell, 22, is accused of gaining access to Palin's account in September 2008 by correctly answering a series of personal security questions. He has pleaded not guilty.
Davies told the court there are people throughout the country, including Alaska, involved in the case. Palin is former governor of Alaska and was John McCain's running mate when the charges were filed.
According to The Knoxville News Sentinel, Davies is trying to keep out as evidence information gleaned from Yahoo and other Internet providers.
He contends the magistrate lacked authority to issue search warrants for entities outside the Eastern District of Tennessee where Shirley presides.
Prosecutors say a law guaranteeing electronic privacy gives the magistrate that authority.
Another hearing is set for March 24.
Kernell's father is Democratic state Rep. Michael Kernell of Memphis.
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