Just a quick update to say that I heard back from the House of Lords Committee on the Mental Capacity Act 2005, who confirmed what others had said to me - that it is not a contempt of court to submit evidence to the Committee about proceedings in the Court of Protection. I contacted the Committee to ask about this because ordinarily disclosing information about proceedings in the Court of Protection which are held in private is a contempt of court (see s12 Administration of Justice Act 1960), and this prohibition has been very broadly interpreted (In the Matter of B (A Child)  EWHC 411 (Fam)). As Wanda Maddocks could tell you, it is also enforced.
Happily, evidence submitted to the House of Lords Select Committee is protected by an old constitutional guarantee of Parliamentary Privilege, which the clerk of the Committee kindly explained in her email and said I could reproduce here for you to read:
Witnesses’ remarks made in solicited written or oral evidence to select committees are protected by parliamentary privilege. This means that witnesses cannot be prosecuted for what they say in written or oral evidence to a committee; and evidence to a committee could not be used in court to support a prosecution or civil suit. However, it is worth noting that it is only in the context of parliamentary proceedings that the evidence is protected. Parliamentary privilege does not protect a witness if they repeat their evidence outside Parliament.
Given the sensitivities of the circumstances, the Committee will wish to consider how, if at all, to publish the evidence received. That will depend in part on the nature of what is submitted.So, if you have stories about experiences of proceedings in the Court of Protection that you would like to share with the Committee, you can submit written evidence to them. Don't forget though, this protection doesn't apply if you publish or disclose this information to anybody else. Even once you've written to the Committee, it could still be a contempt to tell other people or the media about the proceedings, or stick your evidence on your blog or whatever. Just to repeat that: just because you are protected when telling the Committee, doesn't mean you are protected telling anybody else. Furthermore, the Committee may choose to redact your evidence, or not to publish it at all, as Parliamentary Privilege must be exercised responsibly. Please remember (if you are reading this in the future)*, when the Equality and Human Rights Commission open their inquiry into the deprivation of liberty safeguards, this privilege will not apply.
In addition, if the Committee decided on the basis of a written submission to call an individual for oral evidence, we would expect that session to take place in private. The Committee would need to consider what record, if any, would be taken of the session.
Just a reminder - here is the call for evidence.
*I mean, obviously you are, but the distant future when the EHRC inquiry opens...