Heffer rejoined The Daily Telegraph in October 2005 as a columnist and associate editor, after having served as a columnist for the Daily Mail from 1995. Martin Newland, the The Daily Telegraph's editor at the time, described the newspaper as Heffer's "natural journalistic home." He left the Telegraph in May 2011 to "pursue a role in journalism and broadcasting" and "complete a major literary project". It had been speculated that his departure had been prompted by his constant attacks on David Cameron's government, of which the Telegraph is generally supportive.
Heffer has written biographies of the historian and essayist Thomas Carlyle, the composer Ralph Vaughan Williams, and of the politician Enoch Powell (Like the Roman), which was described by The New Statesman as "a lucid and majestic tribute" to the politician.
In September 2010, Heffer published Strictly English: the Correct Way to Write... and Why it Matters, a guide to English grammar and usage. The book met with some negative reception. Writing in the New Statesman, Professor David Crystal observed that although it contains valid points about ambiguity, honesty and importance of clarity, inconsistencies permeate the book. In a review for Times Higher Education, Geoffrey Pullum described Heffer's claims about grammar as "staggeringly erroneous" and his approach as "intellectual abdication", concluding that "Heffer should be ashamed of himself, and Random House should be ashamed of this book."
Heffer has since rejoined the Daily Mail and edits a new online comment section, called RightMinds, of the paper's online edition. Introducing the new site, the Mail announced that 'MailOnline's new web community for politics, current affairs and controversy' would allow readers to 'have your say on all of the opinions expressed on the site. Every article and blog invites your comment'.
Heffer had a brief flirtation with the hard left in his teenage years, but had abandoned his views by the time he went to university, although he admits he still has a lingering affection for several past figures of the left, such as Tony Benn. When Benn's wife Caroline Benn died in November 2000, Heffer wrote a tribute to Benn in the Daily Mail. He now is very critical of both the European Union and New Labour.
Heffer is a social and constitutional conservative. He supported the retention of Section 28, opposed the equalisation of the age of consent and the liberalisation of laws on abortion and divorce. He opposed the removal of hereditary peers from the House of Lords in 1999, and has also written about the decline of tie-wearing among British men. In August 2002, Heffer blamed "liberal society" for the murders of Holly Wells and Jessica Chapman.
In July 1995, he threatened to resign from the Daily Mail if it supported John Major in the leadership contest. Like many right-wing Conservative MPs, Heffer backed John Redwood, though he preferred Michael Portillo to be party leader. In late 1999, Heffer financially contributed to Neil Hamilton's unsuccessful libel action against Mohammed Al-Fayed.
When the Home Office put Heffer on its Law and Order Task Force, left-wing politicians were concerned about the direction that criminal law reform might take, with human rights lawyer Baroness Kennedy saying that the government "had not just lost the plot but was handing the plotting over to their most feared critics."
Heffer has written sympathetically about and backed the United Kingdom Independence Party (UKIP) and Nigel Farage. He has joined calls from fellow journalist Peter Hitchens for the Conservative Party to be defeated and or abolished. He has spoken widely, and on 8 February 2006, he was guest-of-honour at the Traditional Britain Group's Annual Dinner at Simpsons-in-the-Strand.
In 2008, Heffer called for the United Nations to be strengthened: "If the UN ceases to be regarded by the larger powers as a institution to secure the peace of the world and justice therein, then that holds out all sorts of potential dangers." On 27 May 2009, Heffer threatened to stand as an independent against Sir Alan Haselhurst, his local Conservative MP and a deputy speaker, unless Haselhurst paid back the £12,000 he claimed for work on his garden, as revealed in the Parliamentary expenses scandal. He is a scathing opponent of British Prime Minister David Cameron and modernising elements within the Conservative Party.
- "Portugal has revealed itself to be little more than a banana republic through the handling of this case. Whether you have small children or not, you would be mad even to think of having a holiday there." Simon Heffer writing in The Daily Telegraph about the case of Madeleine McCann, January 2008.
- "The evil that drug dealers do cannot be adequately punished under our present law; I would take a leaf out of China's book, and have them taken out and shot in the back of the head. That isn't going to happen. But using the laws we do have more effectively, applying them with zero tolerance, and making junkies pay – literally – for the damage they do to society would be a start. I fear, though, that it is already too late." Simon Heffer writing in The Daily Telegraph about drug policy, January 2008.
- "If the Government wishes to prime the economy, it should bulldoze the Norris Green estate in Liverpool, where the murderer and his gang live, and split up the gang by redistributing them around the country, preferably to remote islands. Until we stop paying people to be an underclass, we'll have an underclass." Simon Heffer writing in The Daily Telegraph about the case of the murder of Rhys Jones, February 2009.
- "Blame the Hooligans, Not The Stadiums: The problems at Hillsborough, though Taylor was reluctant to say it, was one of hooliganism. However much it may outrage Liverpool, 95 Liverpool fans were killed by the thuggishness and ignorance of other Liverpool fans crushing into the ground behind them. It serves no purpose to prevent the fans who caused the crush from facing that responsibility"
- "Where Hitler failed by military means to conquer Europe, modern Germans are succeeding through trade and financial discipline. Welcome to the Fourth Reich." in: Rise of the Fourth Reich, how Germany is using the financial crisis to conquer Europe, Daily Mail, 17 August 2011.
- "Deceased is a pompous term for dead, often misappropriated as a genteel euphemism." Strictly English, p. 154. "Death is the best example. The lower classes have all sorts of euphemisms for this inevitable event. A loved one (a term that seems only to be used posthumously, or when the reaper is heaving into view or into one's consciousness) may pass away, or pass on, his bereaved family and friends may lose him, he may lose his life, or if they are feeling especially Bunyanesque he may even pass over to the other side, where he becomes deceased or departed. (The last two terms are reminders of how the aspiring, under-educated person passes through a phase in which he feels it is right to imitate the language of bureaucrats, few of whom know how to speak or write English properly.) Joining the heavenly choir is simply Monty Python. To Mitford and her class the person simply dies, and thereafter is dead." Ibid, p. 196
- Heffer, Simon, & Charles Moore (editors), A Tory Seer: The Selected Journalism of T.E. Utley, London, 1989, ISBN 0-241-12728-9
- Heffer, Simon, Moral Desperado: A Life of Thomas Carlyle, London, 1995.
- Heffer, Simon, Power and Place: The Political Consequences of King Edward VII, London, 1998.
- Heffer, Simon, Like the Roman: The Life of Enoch Powell, London, 1998. ISBN 0-297-84286-2
- Heffer, Simon, "Nor Shall My Sword: The Reinvention of England", London, 1999.
- Heffer, Simon, Vaughan Williams, London, 2000. ISBN 0-297-64398-3
- Heffer, Simon: Strictly English: The correct way to write... and why it matters, London : Rh Books, 2010, ISBN 978-1-84794-630-0
- "Columnist Simon Heffer to join The Daily Telegraph". Daily Telegraph (London). Retrieved 5 November 2006.
- Robinson, James (2011-05-11). "Simon Heffer to leave Daily Telegraph". The Guardian (London). Retrieved 2001-05-12.
- Ian Aitken (11 December 1998). "The long road to oblivion. Ian Aitken on Simon Heffer's lucid and majestic tribute to the controversial genius of Enoch Powell". New Statesman. Retrieved 15 March 2011.
- David Crystal (14 October 2010). "Strictly English: The Correct Way to Write...and Why it Matters By Simon Heffer". New Statesman. Retrieved 15 March 2011.
- These ‘rules’ are already broken
- Daily Mail (London) http://www.dailymail.co.uk/debate/index.html
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- Halliday, Josh (13 September 2011). "Simon Heffer launches MailOnline comment website RightMinds". The Guardian (London).
- The Daily Mail – 24 November 2000
- "Simon Heffer on Saturday", Heffer, Simon (2006), The Daily Telegraph, 7 January 2006, London.
- The last thing the House of Lords needs is a mass of elected members, 18 January 2011
- Heffer, Simon (21 December 2005). "Stop apologising for being Christian". Daily Telegraph (London). Retrieved 21 December 2005.
- Helena Kennedy, "Just Law"
-  
- The Daily Telegraph, 9 February 2006, p.22.
- Daily Telegraph, 23 Aug 2008
- Heffer, Simon (12 January 2008). "UK foreign interventions as a middling power". The Daily Telegraph (London). Retrieved 23 May 2010.
- Simon Heffer "MPs' expenses: do the right thing, Sir Alan Haselhurst, or I will stand against you", Daily Telegraph, 27 May 2009.
- Stephen Brook "Daily Telegraph writer Simon Heffer threatens to stand against his Tory MP", The Guardian, 27 May 2009.
- Simon Heffer: "Only a Tory without principles would demonise the Right" Daily Telegraph: 18.05.10: http://www.telegraph.co.uk/comment/columnists/simonheffer/7737948/Only-a-Tory-without-principles-would-demonise-the-Right.html
- Simon Heffer: "Dave will rue the day he betrayed the Conservatives" Daily Telegraph: 21.05.10: http://www.telegraph.co.uk/comment/columnists/simonheffer/7750235/David-Cameron-will-rue-the-day-he-betrayed-the-Conservatives.html
- Heffer, Simon (5 January 2008). "Don't go to Portugal for your holiday". London: The Daily Telegraph. Retrieved 2008-01-05.
- Heffer, Simon (12 January 2008). "Make junkies pay for hospital treatment". London: The Daily Telegraph. Retrieved 2008-01-12.
- Heffer, Simon (12 January 2008). "Gordon Brown's behaviour is simply immoral (sub-heading: Killing Runs in this Dishonest Family)". London: The Daily Telegraph. Retrieved 2008-01-12.
- Sunday Telegraph 1991; quoted in "Media Impact after Hillsborough", Report of the Hillsborough Project
Trevor Grove and Veronica Wadley
|Deputy Editor of the Daily Telegraph
with Veronica Wadley