Report: Mainstream Media Undermined Jeremy Corbyn

Leader of the Labour Party speaks to a huge crowd leading up to the General Election where Labour won the largest vote share since 1997. (The Independent, 2017)

Since Jeremy Corbyn won the leadership contest in September 2015 there was a concerted effort by the three corporations who owned 80% of the British media to scorn, ridicule, fear monger, and tarnish his public image. While there were other factors like the Blairites of the Labour Party working to undermine Corbyn’s leadership, there were other factors as well. How could a politician with policies were very popular among the British public go from friend to foe so quickly? Was there bias against Labour Leader Jeremy Corbyn leading up to the General Elections of 2017 and 2019? Since I have a background in data analysis I decided to find out.

Based on my previous article about media bias against Presidential Candidate Bernie Sanders in the United States, I used the same methodology for this study. An In These Times study of media bias against individual candidates with positive versus negative mentions was used and a separate study which showed 70% of Facebook users read just the headlines. Another source I used was from the London Bourough University which analyzed three weeks of media coverage of the Conservative and Labour Parties in November 2019 and weighted positive and negative mentions based on circulation.

I analyzed positive and negative connotations in the top ten to twelve news headlines from eight sources: The Daily Mail, The Daily Mirror, The Daily Telegraph, The Guardian, The Independent, Metro, The Sun, and The Times. All of these from March 2019 through April 2020 combined had a monthly reach of 258 million (which include phone, desktop, tablet, and print).

Each candidate were assigned a value based on the number of positive or negative mentions for each headline. If an article by the Sun read “Don’t Trust Marxist Labour and Jeremy Corbyn” one point went into the negative column under Corbyn. But if an article from the Sun read read “If Boris Johnson wins today a bright future begins” one column went into the positive column under Johnson. I analyzed them leading up to first the 2017 Election then the 2019 Election.

Because there were less headlines about Jeremy Corbyn and Theresa May leading up to the 2017 General Election the average number of headlines analyzed was in the 9–12 range, adjusted to so both candidate’s positive and negative totals matched up. For the 2019 General Election it was within the 10–12 range.

2017 Election

Three weeks before the Election Labour leader Jeremy Corbyn had 56% negative coverage versus 62% positive coverage for Conservative Prime Minister Theresa May.

When the election campaign started polls indicated an uphill battle for the Labour party. But by mid-May, Labour had eroded the Conservative party’s lead from eighteen to nine points. Theresa May experienced positive coverage in light of the Manchester bombing at the Ariana Grande concert. Meanwhile Corbyn, who was campaigning in person around the country, experienced negative coverage. The Sun and the Daily Mail were the most negative towards the opposition leader. While the Sun and Daily Express were the most positive towards Theresa May.

While the Labour Party was within four points of the Conservatives, Corbyn received 64% negative coverage.

Two weeks out Jeremy Corbyn’s activism was paying off. Labour was surging from double digit deficit to within single digits of overtaking May’s Conservative Party. Despite this success Corbyn received 60% negative coverage. Although Prime Minister May also received negative coverage, it was largely due to her party’s sharp U-turn on the dementia tax and not attending the BBC leadership debate. This combined with Jeremy Corbyn’s very strong performance during the debates may have contributed to his rise in the polls.

One week before the Election and Corbyn still received more negative than positive coverage relative to May.

With one week to go Corbyn’s Labour Party had dramatically closed the gap with May’s Conservative Party in opinion polls. Despite YouGov polls indicating the Labour Party was within single digits of winning many in the media dismissed it, pointing to the shy Tory effect which occurred in 2015. While mainstream news spelled doom and gloom for the Labour Party YouGov continued to show that the Labour Party under Jeremy Corbyn was surging and within striking distance of winning the popular vote.

While the incumbent received 52.1% positive coverage, Jeremy Corbyn received only 41.6% positive coverage. While coverage did try to paint Labour leader Jeremy Corbyn as unreasonable and unfit, it backfired. When Channel 4 reporter Jeremy Paxman interviewed Jeremy Corbyn his confrontational style and constant interruptions of Jeremy Corbyn played to the Labour leader’s strengths and showed how sane he was. The Labour leader during Paxman’s grilling was calm, reasonable, humorous, and thoughtful. That along with his easy-going nature and consistent message of ending austerity resulted in the Labour Party gaining seats for the first time since 1997 and 40% of the vote, the largest since 2001.

2019 Election

Three weeks before the vote Corbyn is approaching 70% negative coverage compared to Johnson whose coverage is slightly positive @ACBC89

Three weeks before the election Labour leader Jeremy Corbyn was getting 32% positive coverage, in contrast to Conservative leader Boris Johnson who received 52% positive coverage. In the polls Labour was at 25% versus 42% for the Conservatives.

Two weeks until the general election there was a persistent negative coverage against Jeremy Corbyn and his negatives would continue to rise. While Corbyn received 70% negative coverage, Johnson received only 51% negative coverage. Labour was dogged with negative coverage even from center left sources like the Guardian as claims of anti-Semitism and his stance to remain neutral on Brexit became constant themes. Meanwhile Boris Johnson who threatened to remove Channel 4’s license for showing a podium of him with a melting block of ice for not attending the leadership debate and tried to avoid an interview with hard journalist Andrew Neil received around neutral coverage.

In the final week three-quarters of the coverage of Jeremy Corbyn was negative versus slightly positive coverage for Boris Johnson @ACBC89

The contrast of the final week before the General Election is very revealing. Opposition Leader Jeremy Corbyn received 76% negative coverage compared to Conservative PM Boris Johnson who received 53% positive coverage. The Daily Mail, The Daily Telegraph, The Guardian, The Sun, and the Times gave the Labour leader 67% or more in negative coverage in the final week before the vote.

In the three weeks leading up to this election Jeremy Corbyn received less than 29% positive coverage versus over 71% negative coverage. Boris Johnson on the other hand got over 51% positive coverage verses slightly under 49% negative coverage. The Labour leader earned more negative coverage than Bernie Sanders did in the United States during the Democratic primary, indicating an institutional bias against center left candidates in both the UK and the US. This bar graph highlighting the Labour party leader’s negatives almost matches with a report by the London Borough University showing negative coverage weighted by circulation.

Five of the eight sources analyzed covered the Opposition leader very negatively before the 2019 election.
Boris Johnson received largely average to slightly above average positive coverage.

Further research reveals that all among all eight news sources, The Daily Mail, The Times, The Sun, and the Daily Telegraph were the most negative, The Daily Mirror and The Guardian were the most favorable towards the Labour Party. For the Prime Minister the Daily Mirror, The Guardian, The Independent, and the Metro were the most negative, the The Daily Telegraph, The Daily Mail, The Sun, and The Times were the most favorable.


This study focused largely on the headlines leading up to the General Election for June 2017 and December 2019. There is a strong correlation between the tone of an article in the headline relative to the tone of an article itself. Because there were more articles written in the 2019 election than the 2017 election, this focuses a little more on the former than the latter. The total number of articles analyzed for the 2017 election was 476, for the 2019 election it was 564.

Out of the 238 articles analyzed between May 18th and June 7th, 2017 Jeremy Corbyn got 58.4% negative coverage versus 41.6% positive coverage. Prime Minister Theresa May received 52.1% positive to 48.9% negative mentions before the vote. Although the coverage for the Conservatives was expected to be slightly positive given they lead by a plurality in the polls, the coverage of Labour was more negative than was expected given Corbyn helped them climb from a double-digit deficit to within two points of the Prime Minister’s party.

Out of the 282 articles analyzed between November 21st through December 19th, 2019, Corbyn received 71.3% to 28.7% negative to positive coverage. Prime Minister Boris Johnson got 51.4% to 48.6% positive versus negative mentions. Coverage for the Labour Party was very negative during this period which coincides with a previous study mentioned earlier that the center-left party was covered the most negative out of five parties studied. Boris Johnson on the other hand was viewed positively by the press. Given the fact all eight sources held a monthly reach of 258 million, this played a big role influencing the outcome of both elections.

Loughborough University studied first three weeks of 2019 election and weighed positive and negative mentions relative to circulation.



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