The Court of Appeal dismissed the defendant's appeal against the refusal to strike out the plaintiff's claim for damages for libel.
The plaintiff, a former Member of Parliament, commenced proceedings for libel against the defendant, complaining of a broadcast made by the defendant in the course of a television documentary programme in January 1997, in which the defendant accused the plaintiff of seeking and accepting from the defendant cash for questions asked by him in the House of Commons.
Those allegations were the subject of an investigation by the Parliamentary Commissioner for Standards (PCS), the results of which were adopted by the Committee on Standards and Privileges (CSP) in a report which was subsequently approved by Parliament. The PCS found that the plaintiff had received cash from the defendant for lobbying services.
Desmond Browne QC and Adrienne Page (Crockers Oswald Hickson) for the plaintiff; George Carman QC, James Price QC and Heather Rogers (D.J. Freeman) for the defendant; Ross Cranston QC, Solicitor General, and Philip Sales (Treasury Solicitor) for the Speaker and Authorities of the House of Commons as interveners.
Lord Woolf MR said that the following issues arose on the appeal: whether the libel action constituted a collateral attack on a decision of Parliament within the principle in Hunter v Chief Constable of the West Midlands  AC 529; and whether the inquiry by the PCS, the CSP's report, and the approval of it by the House of Commons, together or individually, constituted "proceedings in Parliament" for the purposes of article 9 of the Bill of Rights 1689, or of any wider principle which might protect such proceedings from direct or indirect judicial interference.
The principle enunciated in Hunter was a general principle evolved to prevent that kind of abuse of process inherent in the re-litigation of an issue already once fairly and fully litigated in a competent court. The court, therefore, had to judge the procedural quality of the earlier proceedings. However, in relation to the procedures adopted by the PCS, the CSP and the House of Commons, the court was forbidden by article 9 of the Bill of Rights to undertake such a process.
Further, where either House of Parliament or a committee of Parliament enquired into and passed judgment upon some matter external to the House's affairs, the court was not thereby prohibited from looking into the same matter in the course of later defamation proceedings based on a publication outside Parliament.
The inauguration of the PCS and the CSP and their subsequent actions, the inquiry, the reports, and the resolution of the House amounted individually and collectively to "proceedings in Parliament" whether for the purposes of article 9 of the Bill of Rights or of any wider rule which enjoined the protection of such proceedings.
However, the vice to which article 9 was directed, so far as the courts were concerned, was the inhibition of freedom of speech and debate in Parliament that might flow from any condemnation by the courts themselves. The position was quite different when it came to criticisms by other persons of what was said in Parliament. Accordingly, to allow the plaintiff's action to proceed would not contravene article 9.
There was a wider principle, namely that the courts would not challenge or assault, by any order of their own, an assertion of authority issued by Parliament pursuant to Parliament's own procedures. However, that principle did not of itself bar the plaintiff's libel action, which involved no such assertion by the court. The court should only decline to hear the plaintiff's libel claim if it were persuaded that the possibility of a result being arrived at which was inconsistent with the conclusions of the PCS would be to undermine the authority of Parliament.