As the dust settles on the Hamilton affair all agree that the Nolan reforms have been severely tested. Is self-regulation of Parliament working?

  The Nolan committee recommended ending the tired, old and corrupt system of political inquiries into MPs' misconduct, and replacing it with investigations by an independent commissioner. The first commissioner, Sir Gordon Downey, has reported on 35 complaints against members since the reforms were introduced, and all but one have gone unchallenged.

  Nolan recommended that the commissioner should establish if there was a prima facie case to answer. He could then go on to draw conclusions and make judgments. If, on the other hand, there were no agreement on the facts with the accused MP, under Nolan's second recommendation, the case would pass to a subcommittee of the newly created standards and privileges committee for further investigation.

  The subcommittee would then seek itself to establish the facts, and make judgments. If accused MPs were still dissatisfied, under Nolan's third recommendation, they could appeal to the full committee.

  This procedure avoided possible conflicts between the commissioner and the committee, and met requirements of natural justice. Nevertheless, Nolan's second and third recommendations were never fully implemented, as it became clear they would not work.

  In 25 Fayed allegation cases, the committee unanimously instructed Sir Gordon Downey to make a judgment himself. In the Hamilton case this procedure placed the committee in direct conflict with the Nolan recommendations, as Downey and Hamilton could not agree on the facts.

  In line with Nolan's second recommendation the committee could have stopped the commissioner's Hamilton inquiry on 24 February and turned the whole issue over to a subcommittee. This was the stage by which Downey had established that a prima facie case existed.

  It would have meant televised hearings in the Hamilton case in the run-up to the election. For very obvious reasons, there were few Conservatives arguing for it. The committee refused to do it and asked Downey to carry on. And on reflection, I believe we were right to leave it to Downey.

  The use of the subcommittee as an investigative body and perhaps the full committee as an appellate body would have been disastrous. Based on experience I now no longer believe that it is the job of MPs to try other MPs.

  I am neither judge, juror nor lawyer. I do not believe that a committee of parliament stuffed with MPs is capable of conducting the investigative and cross-questioning aspects of an inquiry into members' conduct. In the Fayed case not only were there over 14,000 documents to consider but there was also a large volume of oral evidence. MPs on the committee were simply not equipped to handle an investigation on this scale. We have constituency responsibilities. And the unpalatable truth is that the old select committee on members' interests collapsed under the weight of political interference. Tory whips meddled in its proceedings in the Hamilton, Greer and Grylls inquiries. Allegations have recently surfaced of influence on even the Jonathan Aitken and earlier John Browne inquiries. The proceedings of that committee were about as quasi-judicial as a meeting of the 1922 Committee of Conservative back-benchers.

  I, like a fool, believed that the period of post-Nolan reforms would herald in a period of unblinkered objectivity. Nothing could be further from the truth. The commissioner side of self- regulation worked like a treat, with the presentation of a whole series of highly-regarded reports. But the committee, in the last parliament, despite the excellent chairmanship of Tony Newton, found itself impregnated with politicking.

  The inquiry into allegations of Conservative whips' manipulation of the original Hamilton inquiry was stopped in its tracks by a Conservative majority block on taking further evidence. There were efforts to drag Tony Blair before the committee to answer questions on the Labour Leader's office blind trust: little more than attempts to lay on a televised show trial prior to the election.

  The fact that the trust had been set up in agreement with and on the advice of the commissioner was being conveniently ignored. The inescapable truth is that parliamentary committees, stuffed with politicians, cannot carry out inquiries into members' conduct. They simply go native. Political pressures are too great.

  The role of the select committee on standards and privileges should be limited to ensuring that the quasi-judicial nature of investigations by the commissioner is properly conducted, that a periodic review of the parliamentary code of conduct is undertaken and that appropriate reports are published. Some of us would go much further and add to the commissioner's duties a clear-cut responsibility to carry out enquiries into wider issues of privilege and contempt of parliament. This controversial proposition would meet immense hostility from the old hands in the Commons. But the issue should not be ducked. I can't understand what MPs are scared of when the House of Commons as a whole decides on these matters in the end.

  Of course, the real radical reform would be to give the commissioner responsibility for approving and policing the application of rules governing the holding of assets by ministers including blind trusts.

  But what is the legacy of the Hamilton affair? What can we do to ensure natural justice and credible appeal procedures in the future? The Nolan proposed appeal procedure involved the whole committee. Many now reject this approach because it will not work.

  Others argue that these matters should be settled in the courts. Such a proposition is ludicrous. Rich MPs with pots of money will delay justice. Rich men hire lawyers who know how to work the system, and on occasions they find ways of hiding behind sub judice rules.

  I have argued that, where an appeal is sought against a judgment, and where the standards and privileges committee, by way of a resolution, is prepared to support such an appeal, assessors should be appointed to review evidence and take further evidence in public if necessary. Public access should curtail abuse of such arrangements. It might be possible to include the chairman of the committee, with the judicial assessors, in the review procedure.

  The commissioner and any counsel appointed to the original inquiry could be available to advise on the reasons for the commissioner's original findings. The review body would report its findings and conclusions to the full committee which would publish in the normal way. Such proposals were not designed to provide a quick fix in the Hamilton affair, as has recently been reported. They provide a long-term solution.

  Nolan's independent commissioner reporting to parliament has been a resounding success. All we need now is a little tinkering with procedures and a rethink on appeals that delivers self-regulation that works.