I wouldn't include terms of dismissal in music ministry bylaws. I would just include a catch-all line that indicates that failure to adhere to the rules can lead to disciplinary action including dismissal (or suspension) from the department.
The thing about ministry is that it's really hard to permanently dismiss someone since there's always room for repentance and forgiveness. If a change of heart takes place, you'd have to renege on the dismissal.
I don't have a letter of dismissal, but if I did, it would read something like this:
Dear Sis. Suzie:
According to Section 3.02 of the ABC Church Music Ministry Bylaws, all choir members are required to xyz. As you know, this is important to the function of the music ministry because _____________. Over the past 3 months, we have brought to your attention xx documented occurrences of your failure to xyz. I regret that we have been unable to resolve the issue, but at this time, I will have to suspend you from serving in music ministry for a period of ____ weeks/months/until further notice/indefinitely/etc. If there is anything I can do to help you, I am still available and certainly willing. If you have any questions or would like to discuss this matter, please feel free to contact me.
(And if your bylaws include an appeal process, let Sis. Suzie know that she has a right to appeal, and what the next steps are).
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Dismissal should never be a surprise, so it's important to keep the letter short, sweet and to the point. No need to rehash everything they've done wrong and all that. Just tell them what rule they broke, document in writing that you did bring it to their attention before, and announce the dismissal. Hopefully you will have really tried to work with them before it got to that via verbal warning, first written warning, second written warning, final warning, offering help, etc. Keep in mind that this is ministry, not Corporate America. You have to have laws, but you have to season them with grace. Your goal should be to help, and if the person cannot be helped, then you take action.
