Queen's Speech 2015 Parliament
The EU referendum and free childcare were unveiled in the Queen's Speech as Queen Elizabeth II revealed details of the Tory pledges, while Prince Philip listened Ben Stansall/WPA Pool/Getty Images

David Cameron may have won the general election with a surprise majority for the Conservative Party, but it is a slim one – made slimmer by rebellious and divided Tory backbenches.

A majority in the House of Commons is 326 seats. The prime minister has 331. So his controversial Queen's Speech is packed full of contentious bills that could easily tear through his tiny majority.

It weakens the power of his Conservative-only executive, who may struggle to force through much of the manifesto unless Cameron – aided, perhaps, by an office of bulldog party whips – can keep his backbenchers united and happy.

We shall see, but here are some of the potential battlegrounds ripe for Conservative infighting, gleaned from the 2015 Queen's Speech.

EU referendum

My government will renegotiate the United Kingdom's relationship with the European Union and pursue reform of the European Union for the benefit of all Member States. Alongside this, early legislation will be introduced to provide for an in-out referendum on membership of the European Union before the end of 2017.

David Cameron
David Cameron has promised British voters a referendum on the country's membership of the EUReuters

Right at the heart of the Queen's Speech is the Cameron government's centrepiece: a referendum on the UK's membership of the EU. Cameron promised a vote back in 2012 while he was under attack on two Eurosceptic fronts.

The first was from his anti-EU backbenchers, who were loudly questioning his leadership of their party at a time when Cameron was politically weak as the UK economy looked to be turning for the worse. To pacify them, he committed to an in/out referendum.

And the second was the haemorrhaging of former Conservative voters to populist Eurosceptic party Ukip. Cameron hoped to woo some back and convince doubters not to leave by offering a referendum.

The prime minister wants to stay in the EU but is seeking a number of reforms and a new settlement for the UK. Among them are restrictions on migrants' access to benefits and more progress on completing the single market.

Whether or not he can secure the reforms is not certain, though Cameron is confident his and the UK's interests align with those of his European partners.

But his backbenches are still split on the fundamental issue of Europe, a divide that will widen as the referendum nears and a bitter campaign enlivens.

Moreover, the terms of the referendum are also likely to cause upset. Some want 16-year-olds to be allowed the vote, others do not. Some fear the EU nationals currently living and working in the UK will get to vote. Others believe they should.

The wording of the referendum question will undoubtedly also fuel debate and dispute within the Conservative party. It is going to be a punishing period for Cameron. If he loses the referendum, and the UK leaves the EU, he is weakened as a leader because he is advocating a continuation of our membership.

But if he wins, can his Eurosceptic backbenchers forgive him? Or will they punish him for not only fighting against them on the EU issue, but beating them too?

Snoopers' Charter

Measures will also be brought forward to promote social cohesion and protect people by tackling extremism. New legislation will modernise the law on communications data, improve the law on policing and criminal justice, and ban the new generation of psychoactive drugs.

Theresa May
Theresa May was criticised by privacy rights groups over her Snoopers' CharterReuters

Home Secretary Theresa May has come under fire from privacy rights groups over her draft Communications Data Bill, dubbed the Snoopers' Charter, which wanted to introduce a wave of powers that force companies to hold on to data they have of private citizens.

That bill was killed off by the backlash, which included the Tories' own coalition partners at the time, the Liberal Democrats. But with a majority Conservative government in power, May has revived her Snoopers' Charter ambitions with the Investigatory Powers Bill, which will hand security services what the government calls "the tools to keep you and your family safe".

But critics say this is code for giving the state carte blanche to invade people's privacy without sufficient justification by handing fresh and broader snooping powers to the likes of GCHQ.

On top of the Extremism Bill, which the government says will "combat groups and individuals who reject our values and promote messages of hate" it will give it the powers of banning orders, extremism disruption orders and closure orders.

Human rights charity Liberty says this will curb free speech "under the guise of tackling extremist behaviour".

So why is this a problem for Cameron? Because not all of his backbenchers agreed with the original Snoopers' Charter. Though he has many who are bullish on counter-terrorism, and would welcome more authoritarian legislation to tackle radical Islamism, some are small-state civil libertarians who recoil at the idea that government will have more powers to pry into the lives of private citizens and limit their right to free speech.

Among them is influential MP David Davis, who stood against Cameron in 2005 for the Conservative leadership. Davis, a respected Tory grandee, said in 2014 that May's draft Snoopers' Charter needed a "wholesale rewrite".

HS2

My government will continue to legislate for high-speed rail links between the different parts of the country.

HS2
High Speed 2, known as HS2, could cost as much as £80bn when it is completedReuters

The creation of a second high speed rail network across the country, which will create better links between northern cities and London, is probably the Conservative government's single biggest infrastructure commitment.

The High Speed Rail (London to West Midlands) Bill would give the government the powers it needs to start phase one of the project.

That includes: "Giving the government powers to compulsorily acquire or temporarily take possession of land required for the scheme, and construct and operate the railway."

At an official cost of £43bn and climbing – with some suggesting it could reach £80bn – it is expensive. And given its route through swathes of rural England, it is also hugely controversial in areas of Tory heartland, where the preservation of the countryside is a major issue for residents.

So there is a large contingent of Conservative MPs who represent constituencies where HS2 will pass through or nearby, much to the ire of local voters. They may be even angrier if the government subjects their communities to compulsory purchase orders, forcing them to sell property so HS2 can be built over it.

Rather than bite the hand that feeds, they may well kick up a stink for Cameron as he tries to push the bill through Parliament – which he probably will do with the support of Labour and perhaps the SNP.