Stuck in the middle.....

So there is some "drama" at work right now. It involves my partner and some recent decisions he has made. but unfortunately because it happened at work while I was present in the ambulance I am kinda stuck in the middle. There is now some disciplinary action going on and he is in trouble for what he did. Management questioned me about the incident and I answered their questions. Now he is expecting me to write a letter about the incident and was kind of telling me what he wanted me to say in that letter because he is fighting his punishment stuff. I kind of feel as if he wants my involvement to rely upon my credibility and I am kinda worried about that because I don't want it to affect me in the long run. I want to do whats right, I already answered the questions (and did not lie) and I feel bad for my partner. I do feel that they are kind of over-reacting but I don't really know with confidence what is right and wrong in this situation. My partner made a comment to me about it when it happened (before someone contacted work about it) and now he is saying he was joking but I dont really know if he was.... so its a little frustrating for me! Anyways I don't want to say much more than that, But I do know this has already affected me, and I know that due to his particular current punishment I will continue to be affected for awhile and until it is all worked out. But since he has the association involved (kinda like our version of a union representation) I think I am going to talk to them first about how I feel and see what they want me to do. I think I am going to tell them I am worried that he is using me to try and better his story and I don't want to be in that position. I dont want to hurt my partner and I dont want him to be punished but he just might have done wrong this time... but I dont know for sure! Anyways thanks for letting me vent! I think I need to go pray now!