Legal Question in Constitutional Law in Utah

Court proceedings are public. Allowing a witness to testify the way you want to would defeat much of the purpose of having public proceedings. It is allowed only under extraordinary circumstances, such as when the witness is an undercover law enforcement officer whose cover would be blown by a public appearance in court. Witnesses who are in the federal witness protection program and whose features have been surgically altered for their protection are also allowed to conceal their appearance in court. There are other such circumstances, but they are comparably rare.

You haven't given us any information about your situation or about the case, so I have no idea whether any of these rare circumstances might apply to you. The odds are that they don't.

Talk to the attorney that subpoenaed you.