In the summer of 1661, Agnes Loch, a married woman residing in Sunniesyd, Newton, near Edinburgh, found herself at the centre of a formal legal investigation. While some accounts of the era record her age as sixty, judicial records from her trial designate her as thirty-four years old. Her case, documented under references C/EGD/371 and T/LA/263, was inextricably linked to the testimony of others; she was explicitly named as an accomplice in the trials of Issobell Burnie, Issobell Cauldwell, and Marion Greinlaw. These broader judicial proceedings suggest that Agnes was viewed not as an isolated figure, but as one participant in an alleged network of individuals accused of attending witches' meetings.
The legal process moved with striking speed following her initial detention. Agnes provided a series of confessions throughout July 1661, with recorded statements dated the 6th, 9th, and finally the 29th of July. On that same final day, the High Court of Justiciary convened in Edinburgh to reach a verdict. In a rare procedure, the court travelled to Musselburgh with the Book of Adjournal to finalise the case. Agnes was found guilty of the charges brought against her and was sentenced to death. The following day, 30 July 1661, the sentence was carried out by the customary method of strangulation and burning.