Thornton’s defence rested entirely on his alibi. If he was not in the harrowed field when Mary came through it on her way to her uncle’s, he could not have murdered her. In his brief for Thornton’s barristers Sadler had laid it out clearly: ‘The only point the Prisoner can in this case rest his defence on is the improbability and even impossibility of his committing the offence on account of the very short period of time that did elapse after the deceased left Butler’s house in the morning and before he was seen near John Holden’s house.’ Even if Mary left Mrs Butler’s house as early as four o’clock and reached the pit fifteen or twenty minutes later, Thornton would only have about fifteen minutes to rape and murder her, arrange her belongings on the bank and get to Holden’s farm three and a half miles away.
Even so, it was crucial for the defence to establish that Thornton was seen at Holden’s farm as early as they could and that he had not been running. William Jennens, the Birmingham milkman, confirmed that he had seen Thornton at ‘about half past four o’clock, as near as I could judge, having no watch.’ How did you know what time it was? asked Reader.
A: My wife, who was with me, afterwards asked at Mr Holden, of Jane Heaton, the servant, what o’clock it was. She looked at the clock and told her.
Q: How long was it, after you saw the Prisoner, before your wife asked Jane Heaton what time it was?
A: Before she inquired, and after I saw the Prisoner, we had milked a cow a piece, in the yard, which might occupy us about ten minutes. The cows were not in the yard then, they were a field’s breadth from the house.
Q: And you think this time, in all, took up about ten minutes.
A: Yes, about ten minutes altogether.
Jennens said Thornton was walking ‘very leisurely… quite slow’ but Clarke, for the prosecution, was more interested in which direction he came from: the towing path of the canal or down the lane. ‘I can’t tell that. I did not see him until he was within twenty yards of me,’ said William Jennens but immediately contradicted himself when Reader asked how far down the towpath he could see (‘Three or four hundred yards’) and whether Thornton had come that way (‘I think I must [would] have seen him’).
Martha Jennens also said she had seen Thornton, who was ‘coming along gently’ and corroborated her husband’s account of milking the cows and asking Jane Heaton the time. But to Copley, cross-examining for the prosecution, she admitted that she had had her back to Thornton initially, while she and her husband ‘looked at a cow that was running at a great rate down the lane’ and only saw Thornton when they turned round to look after the animal. She agreed that he could have come along the towpath.
John Holden’s servant Jane Heaton said she rose at 4.30 and as she stood at a window in the farmhouse saw a man walking ‘quite slow’ along the road leading from Erdington to Castle Bromwich. She remembered Martha Jennens asking her the time, and said she told her it was seventeen minutes to five. John Holden junior told the court he had gone to fetch the cows for the Jennens to milk ‘but I don’t know what time they came.’ He claimed to know Thornton by sight and said he saw him two hundred yards from the farmhouse going ‘quite slow’ towards Castle Bromwich.
William Twamley, now totally estranged from William Bedford, spoke about checking John Holden’s clock, which matched his own exactly. ‘I went from thence to Birmingham. My watch was just right with St Martin’s church, and it wanted a minute and a half of the tower clock there.’
The next sighting of Thornton was by the floodgates at Zachariah Twamley’s mill, half a mile from Holden’s farm, when he stopped to talk to his friend John Heydon, who was Mr Rotton’s gamekeeper. Heydon told the court he had left his home at ten to five and went to empty the nets he had put down the night before. He heard Rotton’s stable clock strike five and saw Thornton coming along the footpath towards Castle Bromwich five minutes after that. Heydon asked him where he had been. ‘Taking a wench home,’ he replied (according to his own statement, Thornton had not actually done that; he claimed he had parted with Mary near Greensall’s farm while he relieved himself in a field, and did not see her again). John Woodcock, Zachariah Twamley’s miller, said he saw Thornton and Heydon talking. ‘From a calculation I have since made, it must have been about ten minutes past five.’ When questioned by Copley for the prosecution, he explained, ‘I went into the mill the first thing, and when I came out again, I heard Mr Rotton’s stable clock strike five. I then went into a piece of wheat belonging to Mr Smallwood, and came back again. It must have been soon after five when I saw the Prisoner come up to Heydon at the floodgates, for I have walked the ground over since, and it takes me just ten minutes at a gentle pace.’
Joseph Webster’s brother-in-law John William Crompton told the court that he had measured the clock at Castle Bromwich church and found it to be a quarter of an hour fast; James White, at work at Wheelwright’s bank, half a mile from Twamley’s mill, saw Thornton at 5.20 going towards Castle Bromwich. Finally, William Coleman, Mary’s grandfather, truthfully stated that Mary had not slept at his house on the night of 26 May. Calling him was an act of cruelty on the part of the defence. It added nothing to Thornton’s defence, but established the victim as a liar.
It was six o’clock. All that remained now was for the judge to deliver the charge to the jury and to sum up the evidence.
Justice Holroyd started with worthy exhortations not to convict on anything but the facts and to ignore any prejudice. It was not a question of whether the prisoner had moral responsibility for Mary’s death, he said, but whether he had actually murdered her. He acknowledged that many prosecutions were built on evidence that was entirely circumstantial, as this one was, but at the same time, ‘facts could not be altered; they always spoke for themselves, and would not give way to opinions. But these circumstances… must be clear, full and perfect.’
The issue of whether the sex took place before or after Mary went to Mrs Butler’s to change her clothes was key. If the jury thought it took place before, the sex was consensual because Mary showed no distress when she was with Hannah. They should remember that if that was the case, Thornton would have had no motive to kill her. ‘If there was no rape, and the intercourse took place with the consent of the deceased, whether that consent was obtained by great importunity or not, that would make it less likely that [Thornton] would commit murder,’ he said. Importunity was not regarded as violence, but was a step up from seduction or emotional pressure and arose from Thornton’s need to complete a sexual act that Mary, by cavorting in fields, had semi-promised. Holroyd had encapsulated the essence of rape law. It was, after all, almost impossible to rape a woman. Any coercion to overcome Mary’s understandable reluctance fell within the bounds of legality.
If the sex took place after Mary had changed her clothes, Holroyd conceded only that it was more likely to be rape. But in any case, if Thornton’s witnesses were telling the truth, he was several miles away when Mary went into the pit. This made ‘what space of time there was for the transactions to take place…very material.’
Holroyd used the plan of the area (we don’t know whether it was the defence or the prosecution’s version) to point out places and distances. In the end, however, it boiled it down to this: ‘It is your duty to consider whether it is possible for the pursuit [of Mary in the harrowed field] to have taken place, and all the circumstances connected with it, and for the prisoner to have reached Holden’s house, a distance of nearly three miles and a half, in so short a time — a period of not more than twenty minutes.’ It was better, he said in conclusion, that the murderer, ‘with all the weight of his crime upon his head, should escape punishment, than that another person should suffer death, without being guilty.’ As for the alibi, it must be ‘clear, certain and well connected, there must be no blank in the chain, or else all would fall to the ground.’
At 8.30pm, twelve and a half hours after the process started, the jury left the courtroom, returning six minutes later to announce a verdict of Not Guilty. For the first time since he had entered the courtroom Thornton betrayed some emotion. The relief showed on his face.
The rest of the trial was a formality. Thornton was charged with rape and, after the prosecution offered no evidence, was again acquitted. He left the court a free man.