An allegation is an accusation with due proof. Most of the time, allegations are made before proof can be verified. This is done as a legal strategy to fluster an opposing party or to otherwise make them aware that someone might have something on them before a formal trial. Allegations cannot be upheld in court without due proof. Any allegation can be used in court then resurfaced later on once proof has materialised. Whatever the case, knowing how to rebuke allegations is something that anyone in the spotlight should know how to do. One of the best ways to do this is in a letter.
Begin the header with a very formal salutation. "To Whom It May Concern," is the standard. This allows the party that you are addressing to know that you are serious about the situation and are not just trying to scare them off. It also allows the opposing party to know that you are professional and are not just a frightened person. The header is the most important part of the rebuking letter because it sets the tone for the rest of the letter.
Continue being professional into the body of your letter. The letter should clearly state that the allegations are false and will not be tolerated. It is also a good idea to remind the opposing party that allegations will not hold up in court without proof. Though the opposing party probably already knows this, it lets them know that you are aware of it and that you have a familiarity with legalities and the practices therein. If nothing else, it helps you sound more intelligent, giving credit to your letter.
Keep the letter simple. The last thing you want to do is give your opponent more ammunition in their argument. Rambling on about anything can allow the opposition to find some slip up in your diction. This can come back to haunt you. This being the case, just keep the letter simple. Any given letter of this kind should go no more than 1,000 words but no fewer than 400.
End the letter as professionally as you began it. Most legal letters of this type are remembered the most by their first and last lines. Keep these lines strong and you should have a sturdy letter. Have the letter proofread by a trusted friend or two before sending it.