From the Court of Appeal documents.
99. Later the appellant said he had decided to shoot his family and he told her that he had discovered that the catch on the kitchen window did not work and he could gain access to the house in that way. The appellant said he planned to leave the address by a different window, which latched when it was shut from the outside.
135. He told the police that there were occasions when he gained entry to his parents' home by way of a number of the downstairs windows including those in the kitchen and the bathroom. He explained that he used a knife to move the catches in order that the window could be opened from the outside.
141. The appellant claimed to have returned to the farmhouse within a day or two of his release from the Police Station, i.e. a day or two from the 13 September, and gained entry via the downstairs bathroom window. He said he had done this because he had left his keys in London and needed some documents for his trip to the South of France.
146. He had the means and knowledge to gain entry to the address, one such route being through the bathroom window.
149. The appellant returned the moderator to the gun cupboard and before leaving the address called his home at Goldhanger, leaving the receiver off the hook, thus lending support to the alibi he would later rely upon. He then left the premises, one available route being to climb out of the kitchen window, banging it from the outside to drop the catch back into position and then cycled home.
151. iv) The appellant's admitted ability to effect covert entry into and exit from the farmhouse and the finding of the hacksaw blade outside the bathroom window.
262. It was the Crown's case that the appellant entered White House Farm, for the purpose of carrying out the murders, by the downstairs bathroom window and left the premises by the kitchen window.
263. Police Sergeant Golding gave evidence that at 2.30 p.m. on 7 August he commenced to secure the ground floor and found all windows to be secure and fastened with the exception of two windows. One was in the ground floor bathroom, which was in a closed position with the catch open. He secured the window by closing the latch. The other was a transom window, which formed part of a casement type window in the kitchen. The transom window was open approximately halfway. He secured the window.
268. The examination of the Farm for entry and exit marks became particularly significant. On the 1 October 1985 Brian Elliott a forensic scientist examined the window catch and surrounding area of the downstairs bathroom/toilet sash window. He noticed that the brass catch had been scratched on the inner edge and that there was damage to the white paintwork on the adjacent faces of the top of the bottom sash and the bottom of the top sash. The white paint on the outside of the window including the outer face of the top of the bottom sash appeared clean and fresh.
269. He concluded that the damage to the sash window and catch was consistent with a thin blade having been inserted between the closely fitting sashes of the window in an effort to force the catch open. Furthermore this attack occurred after the outside of the window had last been painted. There was evidence that the windows had been painted in June and July.
270. It was the prosecution case that the marks on the paintwork had been made by the appellant when entering the Farm during the late evening or early hours of the 6 or 7 August in order to commit the murders.
271. It was the defence case, revealed for the first time at trial, that the appellant made those marks following his release after Police interview on or about 16 September upon his return from London having forgotten his keys. It was of potential advantage to the defence to demonstrate that the window in question was examined on the 8, 9, or 10 September and that at that time no marks were found on the window.
273. ..."They (Robert Boulflour and Ann Eaton) thought the windows could be locked from outside the premises making particular reference to the window behind the bushes by the Geese pond facing towards the tennis court".
This would appear to be the kitchen window and provides the explanation for DC Barlow's examination of the kitchen window.
279. In evidence the appellant stated that he had returned to the farm the night after his release or the night after that – i.e. on the 14 or 15 September. In evidence he said
"After my arrest at Chelmsford I went to London, came back and had not got my key. I needed car documents kept in the office for a holiday and I got in the loo window."
284. On the 12 September, 2 days later he was asked:
"Question: Have you ever got in a window by putting something in between the window frames, like a knife, to move the catch so you could slide the window open?
Question: Which window?
Answer: Downstairs toilet and lounge window". http://www.homepage-link.to/justice/judgements/Bamber/index.html