Kilpatrick's attorneys want to keep the intimate and sexually explicit text messages out of a trial, and at least one outside defense lawyer says the admissibility of such high-tech communications is an unsettled legal question. Even if they are admitted, experts say the defense will exploit any ambiguity in the messages, in the questions the mayor and former Chief of Staff Christine Beatty were asked under oath, and in their answers.

"If the questions were not clear, and that's going to be used to prove the case, then that's another avenue in trying to establish a reasonable doubt," former federal prosecutor Matthew Orwig said Tuesday.

On Tuesday, the usually gregarious Kilpatrick was subdued as he stood mute to eight felony charges of perjury, conspiracy, obstruction of justice and misconduct in office during his arraignment in Detroit. Beatty also stood mute to seven of those charges.

Not guilty pleas were entered for both. They were released on personal bonds and are expected to appear at a June 9 preliminary examination that will determine if they will face trial in Wayne County Circuit Court.