As in the Salem witch trials, chief prosecution witness against the Pendle witches was a young person, a 9 year-old girl, Jennet Device/Davis, youngest member of one of the families on trial. Whether her evidence was credible is a matter of opinion. Whether she understood what she was saying, whether she was coached or was trying to please Roger Nowell are all debateable.
Jennet, as an adult, suffered the same fate as the rest of her family.