Because if this is a contempt hearing, the judge wants him there in person since he is the subject of the contempt action. Did the judge issue an order denying a motion for telephonic appearance?
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Judges have all kinds of rules. Some make sense. Some do not.
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Some judges have a strict rule against telephonic appearances in any case. It's always easier to judge the credibility and veracity of one's statements when the subject appears in person. Many judges realize this and therefore have established this rule.
Telephonic hearings are a privilege, not a right, and it's difficult for judges to evaluate the credibility of people (or even know for sure who they really are) over the phone. Besides, maybe the judge wants to put him in jail for being behind on support.
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