While nobody will defend Derek Conway's misuse of parliamentary allowances, it seems that some even disapprove of the large number of MPs legitimately upholding family values in the staffing of their Commons offices.

Yet, the employment of nearest and dearest to open constituents' letters is small change compared with Westminster's history of tax-funded nepotism. After all, it is only recently that the tradition has withered of putting relatives into positions of genuine responsibility.

Earl Grey formed a Whig administration determined to create a more democratic society by passing the 1832 Reform Act. Among the names given preferment were 17 of Grey's relations. Few doubted the talents of Lord Stanley, the new Foreign Secretary in 1866. But it did detract that he had been appointed by a Prime Minister, Lord Derby, who happened to be his father. William Gladstone also recognised hereditary talent, employing as his secretary a certain Herbert Gladstone.

When Robert Gascoyne-Cecil, third Marquess of Salisbury, reshuffled his Cabinet in 1887, he made his largely untested nephew, Arthur Balfour, Chief Secretary of Ireland. Such was the outcry that there are still etymologists sticking to the disputed claim that it popularised the catchphrase “Bob's your uncle”.

Indeed, by the time Salisbury stepped down (in favour of dear nephew Arthur) as Prime Minister in 1902, he had also made Balfour's younger brother, Gerald, President of the Board of Trade (salary £2,000). He had also made his son-in-law, the Earl of Selborne, First Lord of the Admiralty (salary £4,500) and his own son and heir, Lord Cranborne, Under-Secretary at the Foreign Office (salary £1,500). Some wondered whether the Prime Minister was guiding the British Empire or managing the Hotel Cecil.

Even Labour leaders have risked allegations of nepotism. Ramsay MacDonald appointed his son, Malcolm, to his Government. In 1977, when James Callaghan was looking for a new Ambassador to the United States, he looked no farther than his son-in-law, Peter Jay.

With talent like Balfour and Jay, not all these alleged examples of nepotism were necessarily against the national interest. More doubtful was Harold Macmillan's role as a one-man labour exchange for his extended family. Supermac took Britain into the 1960s with a government of 85 ministers, of which 35 were his wife's relations. Seven of them sat in the Cabinet. Amazingly, only one of them, the Duke of Devonshire, had the modesty to admit that his appointment was “the greatest act of nepotism ever”.

At the time, it fell to one loyal Tory MP to spin the news differently: “It is a man of courage who is not afraid to allocate the posts in his ministry regardless of family relationships.”

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