Is it possible this is due to the manner in which questions were posed? For example 'what were you doing on the evening of February 19th 2015' would evoke 'can't remember' in most people.
The police interview process wouldn't pose a question in this way. There is a methodical framework known by the mnemonic PEACE
P reparation and Planning (officer pre-interview),
E ngage and Explain (initial introduction including caution etc),
A ccount (suspects 1st account), clarify (what suspect says - get detail) and challenge (introduce evidence to disprove)
C lose (Interview admin before terminating interview)
E valuation (review interview and decide on next steps)
Or is it another way of saying 'no comment'? Would a solicitor / barrister advise a person to respond 'can't remember'?
The legal advisor can't concoct a story for the client or advise them to lie.
The legal adviser will receive disclosure by the police of some or all of the witness statements, pre-interview. They will then consult privately with their client (soundproof room normally....no bugs!)
It may be that they consider the evidence weak and are therefore likely to advise their clients on their right not to say anything.... although convention is "no comment" "for the benefit of the tape"!
To account for the evidence in the police statements a further statement could be prepared by the solicitor in the clients' words, accounting for the evidence and then handed over at the start of the interview. Followed by "no comment" to any questions.
The third option is to provide a full and frank admission, as in "sing like a canary".
The fourth option is if you are innocent....probably best not playing games and just co-operate, if you have faith in the justice system.
Also, when a person is accused of a heinous crime such as this one, do they get quite heavily medicated whilst either on remand in prison or at home in the community? Some psychiatric medications can render a person barely able to function or interact but may well be needed.
Sedative medication should only be given when there is a clinical need, as with anyone. I know there have been some horror stories with the elderly and severe learning disabilities in the past, so I'd never say never. Although, I've never come across it in prison and I've been in a few
