What kind of evidence does the court admit in order to convict people as witches?

The court arrests people based upon the actions of Abigail and the other girls. If Abigail and the others scream or cry out, those who've been paraded in front of them are arrested.

—Mary Warren speak of Abigail as though she were a saint, to hear her. She brings the other girls into the court, and where she walks the crowd will part like the sea for Israel. And folks are brought before them, and if Abigail scream and howl and fall to the floor—the person‘s clapped in the jail for bewitchin‘ her.