Proffer
（重定向自Profers）
- For the agreement between prosecutor and defendant, see proffer letter.
A proffer is an offer made prior to any formal negotiations.
In a trial, to proffer (sometimes profer) is to offer evidence in support of an argument, or elements of an affirmative defense or offense. A party with the burden of proof must proffer sufficient evidence to carry that burden. For example, in support of a particular argument, a party may proffer documentary evidence or witnesses.