Now we have a new addition to the genre. Mohamed al-Fayed yesterday cited a Commons Trade and Industry Committee report in 1990 as backing his criticisms of Department of Trade and Industry investigations.
True enough, there was some criticism. But on the fundamental issue, which was whether DTI inspectors should be allowed to draw conclusions about the behaviour of people they investigate, the committee was absolutely clear.
The MPs rejected a suggestion from the Bank of England and Lord Alexander, chairman of NatWest (a bank badly bruised by the DTI report on Blue Arrow) that inspectors' reports be confined to establishing the facts.
Had they got their way, most reports would have become meaningless catalogues of events. The whole point of the system is to draw conclusions. Fortunately, the European Court of Human Rights, where the Fayeds have been testing the point, seems to agree.
Board of Trade investigations were always intended to act rather in the nature of an inquest on a collapse or scandal. The idea was both to get to the bottom of what occurred and, by passing judgement on events and criticising participants, to act as a deterrent to others.
Investors in British companies have little enough protection against errant boards of directors. DTI inspectors have often proved powerful public advocates working on behalf of shareholders, searching out abuses and naming those responsible.
It is all very well saying, as Mr Fayed does, that other countries do not have such a system. Few others have the open markets and the near complete separation of management from ownership that we have in the UK.
If DTI investigations are confined to their original purpose, they will always provide a valuable public service. The difficulty creeps in when, as in the Guinness and Blue Arrow cases, they are used as the basis for criminal prosecution.
Here critics are on much stronger ground. It is clearly unfair and a breach of natural justice for interviews obtained by DTI inspectors with far-reaching powers to compel answers to be used as evidence in criminal actions. Since no proceedings were ever launched against Mr Fayed, however, this is not something that need concern him. Let the verdict of DTI inspectors that he lied about his origins and wealth stand.