While Marian Ames is testifying on the stand, we momentarily see the defendant with Marian Ames sitting behind her.
The sales clerk at the bookstore tells Arthur Poe that the "Ordeal" book is $4.95 plus sales tax. Poe hands him a $10 bill. After pushing several buttons on the cash register, it displays the amount of $5.15. If this is meant to be the change due, that is incorrect, as Poe would only be paying $4.85 for the book (tax included), below the original pre-tax amount due. If it is meant to be the total with sales tax, it is incorrect, as that would be 4% sales tax and sales tax in Los Angeles (where the show is set) was only 3% in 1960.
An exterior shot in front of the Sutton house is supposed to be at ten o'clock in the evening, but it is full daylight outside.
The novel "Ordeal" is meant to be a publication of Arthur Poe's journal that he kept during the first part of his imprisonment during the Korean War. The prop books seen are easily 400-500 pages, typeset. A handwritten version of them would be several times the length, hundreds, if not thousands, of pages long. It would be virtually impossible for Poe to have kept such a journal in captivity or carried it with him when attempting escape.