Mr A,
Remember (but you are probably already aware of this, of course) that you cannot go to the LGO (Local Government Ombudsman) with your case until such time as you have 'exhausted' the LA's formal complaints procedure that Jancis mentions. And by the time you've 'exhausted' that procedure you will also be more than exhausted, because it can take several years, especially if you are dealing with a 'serious' complaint.
Then it can take another year or two for the LGO to 'manage' your complaint.
I think they all meanwhile cross their fingers, prolong any formal complaints procedure ad infinitum, hoping that you will recede gracefully into the background, and also - sadly - that your relative will no longer be on this earth.
It's so very easy for some people to intimate that it's all down to the way you smile and achieve a comfy cosy relationship' with your SW, the SS, the LA, the CH, et al. And that if you can't manage to reach that desirable situation, then it must be all 'down to you', but those who have had to walk that path, wearing the shoes that sometimes hurt enormously, know that it ain't always so simple.
An IMCA can be invited to comment on whether someone is being deprived of their liberty - but I'm not sure that it's the role of an IMCA to ensure that the DOLs procedures are being followed to the letter. That must surely be the function of whoever approved the DOL, in the first place. But I'll look into that further, another day.
However, a friend of mine has recently received a huge written apology via the Investigating officer who was investigating his formal complaint on behalf of the LA and on behalf of the PCT and the Foundation Trust and the Care Home - for having involved an IMCA totally inappropriately, without informing the family of the person in care and without 'valid reasons' and also without having made sufficient effort to arrange meetings to resolve the situation. So he's now back where he asked them all to be: talking, and trying to resolve the situation. But they all decided not to accept his invitation, and went their own sour way!
So these mistakes do happen, but you have to challenge them, in writing. Which is enormously tiresome and you will be more than tired of it all by the time you get to a resolution, in the best interests of your father.