The Liberal Democrats will do a lot of talking at their conference in Glasgow this week, so it's worth remembering the single most important truth about them: Nick Clegg has repeatedly said one thing and then done another. Time after time Nick Clegg has tried to distance himself from the failures of David Cameron's government but the truth is he has ditched his principles and voted in Parliament with the Tories all the way.
Here's a top 10:
1. Tuition Fees
Nick Clegg campaigned on a promise to scrap tuition fees if they got into power, and every Liberal Democrat MP pledged to vote against future tuition fee increases. But once in government, Nick Clegg and his MPs voted to treble tuition fees to £9,000,
Nick Clegg campaigned against what he called a "TORY VAT BOMBSHELL" during the election. But it was a bombshell he helped the Tories drop - voting to increase VAT to 20%.
3. Tax Cut for Millionaires
Nick Clegg promised "fairer taxes in tough times", but he didn't deliver them. Instead, he backed a Tory cut in the top rate of tax, giving 13,000 millionaires a tax cut worth an average £100,000 while millions are paying more.
4. Living Standards
Nick Clegg says that "thanks to the Liberal Democrats, the government has been helping people get through these difficult times with measures to make life fairer and easier". The reality is that, with Liberal Democrats in government, things are getting harder - with wages down £1,500 since the election and a million young people out of work.
Nick Clegg and his party backed David Cameron's top-down NHS reorganisation from the start. It was passed thanks to Lib Dem votes, and they share responsibility for wasting £3billion on a top-down NHS reorganisation while more people wait longer in A&Es and over 5,000 nurses are cut.
6. Mansion Tax
In opposition, the Liberal Democrats said they backed a mansion tax. Even after they went into coalition with the Tories, Nick Clegg said "The Mansion Tax is right, it makes sense and the Liberal Democrats will continue to make the case for it. We're going to stick to our guns". Did he stick to his guns? Of course not. When given the chance to stand up for their own principles and vote for a mansion tax, Liberal Democrat MPs voted against it.
7. Constitutional Reform
Nick Clegg said his constitutional reform programme would be "the biggest shake-up of our democracy since the Great Reform Act of 1832". It wasn't. He abandoned Lords reform after Conservative MPs refused to back it, and he failed to deliver reform of the voting system.
8. Sure Start
In May 2010, Nick Clegg promised to protect Sure Start and told voters that "Difficult decisions are going to have to be made in public spending, but Sure Start is one of the best things the last government has done and I want all these centres to stay open". But in Government, the Liberal Democrats have backed cuts to Sure Start - and 558 centres have shut so far.
In the Liberal Democrat manifesto, Nick Clegg promised to put 3,000 more police on the beat. But in Government they backed Tory plans to cut more than 15,000 police officers.
10. Special Advisers
In opposition, the Liberal Democrats said that special advisers "are political jobs, and should, therefore, be funded by political parties". They changed their tune when they got into Government. Nick Clegg alone has sixteen Special Advisers - paid for at the taxpayers' expense.
So whatever Nick Clegg says this weekend, the truth is the Liberal Democrats have not been a brake on the Tories during their time in Coalition. They have voted for the Government's policies in Parliament and must be held to account for these decisions.
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