Received a summons - do I have to appear if I feel unsafe testifying?

I have received a letter from the District Attorney''s office of Boston that "commands and summons" me to be in that city on a certain date for an unknown period of time until the trial is over. The trial is concerning a verbal harassment/threatening (but non-physical) fight. I was not the person who committed the crime, but was with him. I did not say anything to the people he threatened. I was 17 at the time and the officers asked me questions outside of the squad car while my parents were not there. I live in Pennsylvania and can think of no way to make it to Boston. I will be starting college and do not have the money to get up there and stay in a hotel for an unknown amount of time. Do I HAVE to go and testify against this person? Would it be possible to give a statement over the phone or in writing instead? The biggest reason I don't want to appear is that I feel unsafe doing so. The person who committed the crime called my cell phone after being arrested, screaming things at me (including profanities) and texted me 5-10 times after that. I feel uncomfortable going there to testify and feel like it would be very unsafe. FYI: The person who committed this crime is not in jail, so I am not protected in that sense.

You MUST obey a court order---if you do not, they will issue a bench warrant for your arrest for failure to appear.

HOWEVER, you do have the right to contact whomever it was that sent you the summons--the prosecutor, I suspect. Explain to them your reservations, as you did here. Only they have the ability to excuse you from appearing. I wouldn't accept "permission" from anyone other than whomever the summons was from ( presumably, the prosecutor).

Whatever you choose to do, I would advise you not to ignore the summons.