Theresa May will warn online “intimidation and aggression” is threatening democracy in a speech to mark the 100th anniversary of women winning the right to vote.
Social media companies will be forced to take more action to tackle abuse in a bid to stop trolls “coarsening” public debate, the Prime Minister will announce.
On the centenary of the 1918 Representation of the People Act, Mrs May will praise the “heroic campaigners” who won the vote for some British women “in spite of all danger and discouragement – because they knew their cause was right”.
She will ask the public to “consider what values and principles guide our conduct of that debate today” amid widespread concern over the abuse heaped on elected politicians and traded between ordinary citizens.
Internet giants such as Facebook and Twitter will be subject to a new annual internet safety transparency report to provide data on how social media companies are dealing with abusive material.
The report will include information on the amount of harmful content flagged by users, the proportion of material taken down by companies and how complaints are handled.
Mrs May will endorse the recommendations of a report into intimidation last year by the Committee on Standards in Public Life, which called for legislation to shift the balance of liability for illegal content to the social media companies.
Social media firms will be asked to sign up to a code of practice published later this year, while the government will publish an Internet Safety Strategy in the spring.
Speaking in Manchester, the birthplace of suffragette Emmeline Pankhurst, the Prime Minister will say: “Those who fought to establish their right – my right, every woman’s right – to vote in elections, to stand for office and to take their full and rightful place in public life did so in the face of fierce opposition.
“They persevered in spite of all danger and discouragement because they knew their cause was right.
“While there is much to celebrate, I worry that our public debate today is coarsening. That for some it is becoming harder to disagree, without also demeaning opposing viewpoints in the process.
“In the face of what is a threat to our democracy, I believe that all of us – individuals, governments, and media old and new – must accept our responsibility to help sustain a genuinely pluralist public debate for the future.”
Mrs May will warn that failing to tackle online abuse “squanders the opportunity new technology affords us to drive up political engagement” and risks “putting off participation from those who are not prepared to tolerate the levels of abuse which exist”.
Reflecting on the centenary from her position as the UK’s second female elected leader, Mrs May will say: “As the woman at the head of our country’s government, a century after my grandmothers were first given the right to vote, my mission is clear; to build that better future for all our people, a country that works for everyone and a democracy where every voice is heard.”
The Prime Minister will later address a reception at Westminster to launch a year-long Vote 100 programme of events to celebrate a century of female suffrage. All female MPs past and present have been invited.
Labour’s shadow cabinet will meet today at the Museum of London, which is hosting an exhibition on the suffragettes.
In a video filmed outside the broom cupboard in the Palace of Westminster where Emily Davison hid overnight on census day in 1911 as part of the suffragette campaign, Labour leader Jeremy Corbyn will say: “One hundred years later, the struggle for equality continues. There are still too few women in Parliament, women still do not receive equal pay for equal work and many face discrimination in the workplace and in everyday life.
“But the actions of Emily and other campaigners stay with us as we strive to build a truly equal society.”
For the first time, the Parliamentary Archives will display four original Acts of Parliament extending the franchise.
These are the 1918 Representation of the People Act itself, the 1918 Parliament (Qualification of Women) Act allowing women to become MPs, the Equal Franchise Act 1928 which finally gave women the vote on the same terms as men, and the Life Peerages Act 1958 which allowed women to sit in the House of Lords as life peers.