A fruit-and-veg trader is to pack up his market stall for a month after announcing himself as the latest challenger to David Davis in the by-election for his constituency seat.

Eamonn Fitzpatrick, who stood in the 2007 Northampton local election and the 2005 general election, said that he felt compelled to contest the Conservative former frontbencher’s seat of Haltemprice & Howden.

Mr Davis, who was the Shadow Home Secretary, resigned from Parliament in protest at government plans for 42-day detention of terrorism suspects. Mr Fitzpatrick, known locally as Fitzy, said yesterday that he felt compelled to act because Mr Davis’s behaviour was barmy. “I think people will back what I say,” said Mr Fitzpatrick, who is not affiliated to a political party. “I’m not a politician, I’m a fruit-and-veg man, but I’ll certainly have a go and I’ll do whatever it takes.”

In the absence of Labour, Liberal Democrat and UKIP candidates, the eccentric list of likely challengers to Mr Davis now includes a pub landlord and smoking-ban rebel, a political author, an artist and the current holder of the Miss Great Britain title.

Gordon Brown also took on Mr Davis’s argument that 42-day detention was a breach of civil liberties yesterday by suggesting that terrorists using modern up-to-date technologies could not be fought with a “head-in-the-sand” approach.

Without mentioning Mr Davis, Mr Brown strongly defended the use of CCTV, ID cards and the DNA database, declaring that they protected liberties rather than damaged them. Britain must be ready to use 21st-century solutions to deal with 21st-century threats of global terrorism, he argued.

Downing Street insisted that the speech, to the Institute of Public Policy Research, was not intended as a riposte to Mr Davis, but sources acknowledged that Mr Brown believed that some of his critics were clinging romantically to an earlier age when it came to civil liberties.

Mr Brown said that it was time to write a new chapter in Britain’s history that would protect citizens’ security and individual liberties. He said that those people threatening security were ready to use the most up-to-date technology and the challenge was to use technology to counter that. “New technology is giving us modern means by which we can discharge these duties, but just as we need to employ these modern means to protect people from new threats, we must at the same time do more to guarantee our liberties,” he said.

“Facing these modern challenges, it is our duty to write a new chapter in our country’s story: one in which we both protect and promote our security and our liberty, two equally proud traditions.”

Mr Davis’s decision to force a by-election in Haltemprice & Howden is likely to cost the public at least £95,000. The money will ensure the smooth running of the democratic process in the East Yorkshire seat. Each candidate will be entitled to spend up to £100,000 of his or her own money, including donations, on expenses during the forthcoming campaign.

In addition, the Government will foot the bill for all the additional costs associated with the by-election.

Three years ago, the general election contest in Haltemprice & Howden cost East Riding of Yorkshire Council £95,520, which it was able to reclaim in full.

Staffing payments amounted to £40,000, while the printing of poll cards and ballot papers added a further £10,000. Transport costs were £6,000 and rooms were rented for £16,000. An additional £23,000 was spent on stationery, postage, telephone and bank charges.

All these costs will have to be met during the by-election campaign, plus whatever it costs the police to keep an eye on the count, which is likely to be at a Hull leisure centre.

Mr Davis is eager for an opponent of substance, but not even the British National Party is willing to add its name to the list of fringe parties standing against him. Simon Darby, the BNP’s deputy leader, said yesterday that the far-right party shared Mr Davis’s opposition to the Government’s 42-day detention plan for terrorism suspects.

“We would argue that these people [jihadist extremists] should not be in the country in the first place, but if the price we have to pay for the accommodation of millions of immigrants is the scrapping of our ancient rights, then it is not a price worth paying,” he said.

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