Frederick Bywaters and Edith Thompson were jointly charged at the Old Bailey with the murder of Percy Thompson, the woman's husband. Mrs. Thompson had written a long series of letters to Bywaters, who was at sea. In these letters were direct references to alleged attempts which she represented herself as making on the life of her husband.
When read in Court, these letters produced a great effect upon the jury. Nevertheless, the case for the prosecution was a weak one, inasmuch as there was no witness of the murder, except possibly Mrs. Thompson. But Mrs. Thompson insisted on going into the witness-box, and, under a searching cross-examination, she made some damaging admissions.
Both were found guilty. If Mrs. Thompson had not gone into the box it is unlikely that the jury could have convicted Bywaters of anything more than manslaughter, or that they could have convicted her at all.