This is the 4075th most frequent French word.
comparu
"Comparu" means "appeared" or "presented oneself," often in a legal context referring to someone who appeared before a court.
The verb 'comparu' is the past participle of 'comparaître' and is used in this sentence to indicate that the subject ('Il') appeared formally before an authority.
Il a comparu devant le tribunal hier matin.
He appeared before the court yesterday morning.
Again, 'comparu' functions as a form of the verb 'comparaître,' demonstrating that the subject ('Elle') had presented herself in previous occasions before a decision was made.
Elle avait comparu plusieurs fois avant d'être acquittée.
She had appeared several times before being acquitted.
In this instance, 'comparu' is used to describe the action undertaken by 'Les deux témoins' to formally provide their presence in the court of law.