Ben is charged under s.1(2)(b) Criminal Damage Act 1971 because without lawful excuse he destroyed or damaged property, intending by the destruction or damage to endanger the life of another or being reckless as to whether the life of another would be endangered. It is alleged that Ben started a fire at his family home by posting a burning rag through the front letter box after being kicked out by his wife, Jackie. Jackie had discovered that Ben was having an affair with her younger sister, Maureen. The prosecution allege that Ben set fire to the property when the house was in darkness, and he thought everyone was asleep in bed. The hall carpet had been set alight. Luckily the smoke alarm went off and Jackie, her elderly Mum, Rosemary, and her two young children, Alice and Lucy, were able escape by the back door. Ben has pleaded not guilty to the charge under s.1(2)(b) Criminal Damage Act 1971.He intends to call Maureen to give evidence, as she will confirm that he was with her at her home at the time the fire was started. She has made a statement to Ben's solicitors confirming this. The prosecution intends to call Jackie to give evidence. She is fearful of Ben and of giving evidence against him. The prosecution also intends to call Rosemary, who is 82 years old and has recently been diagnosed with Alzheimer's disease, and Alice and Lucy (4-year-old twin sisters). Lucy has delayed speech for her age.

You are the trial judge. (a) Determine on the issues of both competence and compellability in respect of all potential witnesses.

(b) Give judicial direction upon any relevant subsidiary issues as to how the evidence should be given.

(c) During her evidence in chief, Maureen testifies that she got the date confused because Ben definitely did not stay at her house on the evening of the fire. What options are available to the defence?