In 1929 my great-grandfather Isaac Foot introduced one of the first legal aid acts in Parliament, the Poor Prisoners Defence Act. He was a solicitor in Plymouth as well as the Liberal MP for Bodmin, and one of his clients, a poor girl, was facing a murder charge with no financial support in the magistrates court. ‘A prisoner who is without means,’ he said, ‘ought to be in no worse position to establish his innocence than a prisoner who is able to pay.’

Isaac had five sons and two daughters. Three of the sons – Dingle, John and Christopher – followed him into the law. Michael became a journalist. Dingle, the eldest, was a barrister who defended civil liberties in the courts of Commonwealth countries. As the Liberal MP for Dundee he also supported extending the right to challenge unfair government legislation, the process known today as judicial review.

In the 1945 general election, Isaac, Dingle and John Foot all stood as Liberals and were expected to win. All went down to defeat. Michael, the outside chance as a Labour candidate, won in Plymouth Devonport.

The 1949 Legal Aid Act was founded on the principles of Isaac’s 1929 bill. Introducing the act, the attorney general, Hartley Shawcross, said it would ‘open the doors of the courts freely to all persons who may wish to avail themselves of British justice without regard to the question of their wealth or ability to pay.’

Following his work as chair of the Immigration Advisory Service, John was made a Liberal peer in 1967. Speaking in the Lords in 1978, he said:

The brutal and plain fact of the matter for the majority of people in this country today is that unless they are fortunate to have behind them the assistance of some organisation such as a trade union, the doors of British justice are closed and locked. The fact of the matter is that over the last 20 to 25 years the legal aid scheme has been bleeding to death.

His protestations helped introduce the 1979 Legal Aid Act, which gave access to civil legal aid to 70 per cent of families.

Chris Grayling, the justice minister (and the first lord chancellor without any legal training), has set about dismantling the principles of justice established over the last 100 years. He wants to remove legal representation for prisoners, other than assistance for parole; to undermine applications for judicial review by making it harder for them to get funding; and to deny civil legal aid to anyone who has not been resident in the UK for a year (the recent allegations of sexual assault at Yarls Wood Detention Centre came to light with the help of a legal aid lawyer).

Grayling has not had it all his own way. He tried to introduce price competitive tendering (PCT) that would have denied people without means the right to choose their own solicitor. Companies such as the haulage firm Eddie Stobart announced they were going to bid for contracts for criminal defence. But protests outside Parliament, 16,000 responses to the consultation exercise and a petition organised by a Devon solicitor that collected 100,000 signatures helped to see off PCT.

Grayling still intends to cut criminal legal aid by 17.5 per cent across the board, however. This could lead to a cut of a third to rates for police station work in London.

I’ve been working in criminal legal aid for 15 years and have never seen the rates increase. No one in my firm has had a pay rise for five years. The cuts will inevitably lead to a serious decline in quality of representation, with many firms going to the wall. It will also mean PCT through the back door, because only large enterprises employing low paid caseworkers will be able survive on such rates.

My father Paul dedicated much of his life to fighting to overturn miscarriages of justice. He worked for 17 years on the Bridgewater Four case, supporting Ann Whelan (the mother of Michael Hickey, one of the four) and the campaign to release the men. The campaign won. Paul worked very closely on the case with his friend Jim Nichol, one of the best appeal lawyers in the country. If Grayling’s cuts had been enforced back then, there is no way that Nichol would have been able to afford to do the years of intensive, low paid investigative work on that (or any other) appeal: appeal work is often subsidised by the kind of case work that is to be heavily cut.

One of my cases went to the Court of Appeal last year. Sam Hallam, a young man from Hoxton, was released from prison after serving eight years for murder. He had not even been at the scene of the crime. The work that I did for a year on that case would have been near impossible in the world that Grayling wants to create.

This summer, I helped to set up the Justice Alliance, a coalition of more than thirty organisations brought together by the London Criminal Courts Solicitors Association. The momentum of the campaign led the Liberal Democrats to vote unanimously against the legal aid cuts at their conference in October. On 1 November, the Justice Alliance delivered a letter to Nick Clegg signed by more than 100 organisations calling on him to implement his conference policy against a government that has no mandate to assault legal aid. Indeed, you would be hard-pressed to find anyone who supports Grayling’s proposals. At a parliamentary debate on 27 June, only two Tories out of 32 speakers were in favour of them. Grayling wasn’t there.

The Justice Alliance letter to Nick Clegg was received by Simon Hughes, who said he welcomed any further representations. On 15 November we sent Nick Clegg 100-word testimonials from more than 100 organisations across the country, including Liberty, Justice, the Howard League, Unite, the Children’s Society, MIND and the Refugee Council. All expressed their deep concern about the proposed attacks on legal aid.

There will be no parliamentary vote on whether or not Grayling’s proposals should be introduced. The issue is now urgent as prison legal representation is set to be slashed at Grayling’s whim in December, with other cuts timetabled not far behind. The future of our legal system rests in the hands of the Lib Dems. The party’s members haven’t forgotten the Liberal tradition of providing access to the courts for the most vulnerable. I just hope that Clegg and his cabinet colleagues remember it too.