Character references are normally handed-up to a court during
the sentencing hearing; which is when the court decides the penalty
that will be imposed on a defendant.
These references are an important way to show the defendant has
accepted responsibility and shown remorse for their conduct by not
just pleading guilty (in the case of a guilty plea), but by
admitting it to those who are important and/or close to him or
her.
Those who provide such references – who is known as
'referees' – should in fairness be made aware of the
whole of the circumstances relating to the person to whom they are
attesting before they 'put pen to paper' and vouch for
another's character.
It stands to reason, then, that a character reference should
make clear that the referee is aware of the document's intended
use.