Andrew Turner was a church minister in the parish of Erskine. He was twenty nine years old, and a close witness to the trials endured by Christian Shaw in Bargarran. He would testify that he witnessed her being bitten on the arms by invisible forces, bites that left marks that he could inspect closely. He also declared that he saw the young girl produce hair and pins from her mouth, with nobody close by who could deliver them to her, while she complained that Katherine Campbell, the household maid, was thrusting them down her throat.

Turner testified that he saw Christian Shaw display unnatural physical symptoms, including her head twisting about towards her shoulders, her stomach swell to incredible proportions, and bruises appear on her leg despite no individual being close enough to deliver any blows to her. Turner stated that the young girl named all of the seven accused as being directly responsible for her physical symptoms, while at the same time acknowledging that some of them had longstanding reputations in the community for witchcraft.

He also declared that when Katherine Campbell was apprehended, she said that she hoped the devil would never let Christian Shaw get better. Turner was also present at Bargarran House when Margaret Lang arrived in order to defend herself against the girl's accusations. He confirmed the story that Christian Shaw had been spellbound into silence by Lang. Turner's evidence is all the more telling given that it was said that he was of the opinion that Margaret Lang was "under good repute, and not the least suspected for witchcraft, or any ill, but esteemed a great Christian." This was before she had been accused by the laird's daughter.