To write a letter to a committee, address the letter to the committee as a whole and not to an individual on the committee. Only send one copy as the committee secretary makes copies for the all who need to see it.
Make a clear plan before writing the letter, outlining points you need to make to achieve the purpose of the letter. Format the letter with a standard or formal letter layout. Begin the letter with an introduction that explains who you are and why you are contacting the committee. This is an important step even if you already know some of the committee members because they may not otherwise share what they know with their fellow members. Make sure the tone you use in the letter is calm and concise, regardless of the content.
Keep your wording clear and straightforward, avoiding jargon, cliché and unnecessary filler. Keep the letter on topic, factual and honest, especially if the letter is about another person. The letter should be as short as possible while still containing every point you hope to make. Conclude with a brief summary of the points you expressed, especially if the matter discussed is complex. Edit the letter, recheck the format, and make a copy for your own records before sending it.