Wiktionary
alt. (context legal English) one who commands or counsels an offense, not being present at its commission. n. (context legal English) one who commands or counsels an offense, not being present at its commission.
WordNet
n. a person who procures or advises or commands the commission of a felony but who is not present at its perpetration
Usage examples of "accessory before the fact".
I was what you'd call an accessory before the fact and an accessory after the fact.
He sat in the armchair, and indulged in a fantasy in which he was arrested with Austin as an accessory before the fact.
The grand jury presently indicted Luigi for murder in the first degree, and Angelo as accessory before the fact.
First, it was held as a crucial party to the crime and an accessory before the fact.
She could probably be charged only with being a minor part of a gang, maybe an accessory before the fact.
Whoever started it would keep quiet when the real news arrived for fear of being implicated in a conspiracy as accessory before the fact.
You could, depending on the outcome, be considered an accessory before the fact.