Michael Howard is putting the issue of trust at the centre of the Conservative general election strategy.
Howard says he owes his life to Britain
In his 47-minute speech to the annual Tory conference, he admitted the last Conservative government broke promises and said that cannot happen again.
He also said crime would be the first problem he would tackle in government, declaring: "The gloves will come off."
The Tories have been buoyed by news that UKIP's chief backer will not bankroll the party's election campaign.
Paul Sykes, who has donated £1.4m to UKIP, says he thinks the party will achieve little more than unseat Tory MPs.
The Yorkshire businessman says he has not yet decided to give money to the Tories, although he thinks their European policies have improved.
Mr Howard told his party he would set a date for a referendum on the proposed EU constitution on his first day in government.
And he said the Tories wanted out of the European social chapter and common fisheries policy as part of bringing powers back from Brussels.
Mr Howard hit a personal note as he described how his mother-in-law had died from a hospital-acquired infection and how his grandmother had been killed in a Nazi concentration camp.
He said he would have been one of those killed in a concentration camp if it wasn't for Winston Churchill and for Britain: "I owe my life to Britain... I want to give Britain just a tiny bit back for what Britain has given me."
The speech unveiled no new policies but Mr Howard offered 10 words to explain why people should vote Tory: "School discipline, more police, cleaner hospitals, lower taxes, controlled immigration".
He pledged to prevent Labour third term tax rises and declared: "Be in no doubt, when I can, I will cut taxes."
Trying to raise party spirits after the disappointing Hartlepool by-election result, he said a Tory government would only promise what it could deliver.
"People are fed up with politics because politicians have let them down," he said.
"Politicians - all politicians - have made promises they have failed to keep.
"In 1992 we promised to cut taxes year on year. But we put them up.
"In 1997 Labour said that there would be no tax increases at all. They put them up. Not once, not twice but sixty-six times. Sixty-six broken promises."
Mr Howard said accountability was the key to rebuilding faith in politics.
"In the real world, if you say you're going to do something, you do it and if you screw up, you can lose your job," he said.
'No dodgy facts'
Shadow ministers are spending the week setting out strict "timetables for action" detailing exactly what they would do and when they would do it.
Mr Howard said the move put "us on the line in a way no government has ever been before".
"Everyone will be able to hold us to account. No dodgy facts and figures - we'll have no place to hide," he said.
"I will choose my Cabinet because I expect them to deliver and if they don't, I'll replace them with people who will."
In his first annual conference speech as party leader, the former home secretary promised a "war on crime", saying police officers are being saddled with too much paperwork.
"We need a government that will stand up for the silent, law abiding majority who play by the rules and pay their dues," he said.
Among the measures he listed was an end to Labour's early release scheme for prisoners, an extra 5,000 police officers a year and more prisons.
Mr Howard repeated his attacks on Labour for inefficiency and waste.
"Billions of pounds of their money have been spent on education, but much of it has been wasted on bureaucracy," he argued.
Pledging to offer everyone the sort of choice that currently only money could buy, Mr Howard said: "That's what I call social justice."
He went on: "Choice and competition raise standards in every field of human activity. Schools and hospitals are no different."
On international affairs, he said he still backed the decision to go to war in Iraq but renewed his claim that Tony Blair had not told the truth.
He asked: "Could the British people trust him a second time?"
Cabinet Office Minister Ruth Kelly said the speech had been incredibly light on detail and had missed the chance to reach out to the centre ground.
"What we saw today is a a real lurch to the right in a desperate attempt to bring back voters from UKIP."
UKIP MEP Robert Kilroy-Silk said the Tories needed at least to offer a referendum on British membership of the EU.
Liberal Democrat chairman Matthew Taylor said Mr Howard knew all about broken promises from his time in government.
"Michael Howard's Conservatives now hint at tax cuts they can't afford except by cutting public services," he said. "No wonder they are falling in the polls."