Question: The co-founder of the Women's Social and Political Union was arrested for assault and obstruction in what year?

full_context: Document 1: Mary Elizabeth Lease: Mary Elizabeth Lease (September 11, 1850 – October 29, 1933) was an American lecturer, writer, and political activist. She was an advocate of the suffrage movement as well as temperance but she was best known for her work with the Populist party. She was born to Irish immigrants Joseph P. and Mary Elizabeth (Murray) Clyens, in Ridgway, Pennsylvania. In 1895, she wrote "The Problem of Civilization Solved", and in 1896, she moved to New York City where she edited the democratic newspaper, "World". In addition, she worked as an editor for the "National Encyclopedia of American Biography". Mary Elizabeth Lease was also known as Mary Ellen Lease. She was called "Queen Mary" (after the British Queen consort, Mary of Teck), "Mother Lease" by her supporters and "Mary Yellin" by her enemies. Lease died in Callicoon, New York.
Document 2: Angelina Grimké: Angelina Emily Grimké Weld (February 20, 1805 – October 26, 1879) was an American political activist, women's rights advocate, supporter of the women's suffrage movement, and besides her sister, Sarah Moore Grimké, the only known white Southern woman to be a part of the abolition movement. While she was raised a Southerner, she spent her entire adult life living in the North. The time of her greatest fame was between 1836, when a letter she sent to William Lloyd Garrison was published in his anti-slavery newspaper, "The Liberator", and May 1838, when she gave a speech to abolitionists gathered in Philadelphia, with a hostile crowd throwing stones and shouting outside the hall. The essays and speeches she produced in that two-year period were incisive arguments to end slavery and to advance women's rights.
Document 3: Emmeline Pankhurst: Emmeline Pankhurst (née Goulden; 15 July 1858 – 14 June 1928) was a British political activist and leader of the British suffragette movement who helped women win the right to vote. In 1999 "Time" named Pankhurst as one of the , stating "she shaped an idea of women for our time; she shook society into a new pattern from which there could be no going back". She was widely criticised for her militant tactics, and historians disagree about their effectiveness, but her work is recognised as a crucial element in achieving women's suffrage in Britain.
Document 4: British Women's Temperance Association: The British Women's Temperance Association (BWTA) was founded following a meeting in Newcastle upon Tyne in 1876 featuring American temperance activist "Mother" Eliza Stewart. Margaret Bright Lucas, who toured with Stewart during these meetings, was elected BWTA president in 1878. A follower of American temperance since visiting the country in 1870, where she was warmly received as "John Bright's sister", she also supported peace and anti-prostitution work, and served on the executives of the National Society for Women's Suffrage and the Ladies' National Association. Her main concern being temperance, she remained BWTA president until her death.
Document 5: Emily Davison: Emily Wilding Davison (11 October 1872 – 8 June 1913) was a suffragette who fought for votes for women in the United Kingdom in the early twentieth century. A member of the Women's Social and Political Union (WSPU) and a militant fighter for her cause, she was arrested on nine occasions, went on hunger strike seven times and was force fed on forty-nine occasions. She died after being hit by King George V's horse Anmer at the 1913 Epsom Derby when she walked onto the track during the race.
Document 6: Christabel Pankhurst: Dame Christabel Harriette Pankhurst, DBE ( ; 22 September 1880 – 13 February 1958), was a British suffragette born in Manchester, England. A co-founder of the Women's Social and Political Union (WSPU), she directed its militant actions from exile in France from 1912 to 1913. In 1914 she supported the war against Germany. After the war she moved to the United States, where she worked as an evangelist for the Second Adventist movement.
Document 7: Caroline Neville Pearre: Caroline Neville Pearre (1834-1910) began the Christian Women's Board of Missions in 1874 after being called to do so during her morning prayers. Pearre was living in Iowa City, Iowa at the time, having taught at Christian colleges in Missouri, Kentucky and Ohio. The wife of a Disciples of Christ pastor, Pearre organized a missionary society in her own church in Iowa City. Friends of hers in other Christian churches organized similar missionary societies in their churches. These various societies united and formed the American Christian Missionary Society which became the Christian Women’s Board of Missions (CWBM).
Document 8: Jane Addams: Jane Addams (September 6, 1860May 21, 1935), known as the "mother" of social work, was a pioneer American settlement activist/reformer, social worker, public philosopher, sociologist, author, and leader in women's suffrage and world peace. She co-founded, with Ellen Gates Starr, an early settlement house in the United States, Chicago's Hull House that would later become known as one of the most famous settlement houses in America. In an era when presidents such as Theodore Roosevelt and Woodrow Wilson identified themselves as reformers and social activists, Addams was one of the most prominent reformers of the Progressive Era. She helped America address and focus on issues that were of concern to mothers, such as the needs of children, local public health, and world peace. In her essay “Utilization of Women in City Government,” Jane Addams noted the connection between the workings of government and the household, stating that many departments of government, such as sanitation and the schooling of children, could be traced back to traditional women’s roles in the private sphere. Thus, these were matters of which women would have more knowledge than men, so women needed the vote to best voice their opinions. She said that if women were to be responsible for cleaning up their communities and making them better places to live, they needed to be able to vote to do so effectively. Addams became a role model for middle-class women who volunteered to uplift their communities. She is increasingly being recognized as a member of the American pragmatist school of philosophy, and is known by many as the first woman "public philosopher in the history of the United States. In 1889 she co-founded Hull House, and in 1920 she was a co-founder for the ACLU. In 1931 she became the first American woman to be awarded the Nobel Peace Prize, and is recognized as the founder of the social work profession in the United States.
Document 9: Rachel Barrett: Rachel Barrett (12 November 1874 – 26 August 1953) was a suffragette and newspaper editor born in Carmarthen, Wales. After attending the University College of Wales in Aberystwyth she became a science teacher. In 1906 she quit her job after hearing Nellie Martel speak on women's suffrage; she then became a member of the Women's Social and Political Union (WSPU) and moved to London. In 1907 she became an organiser for the WSPU and after Christabel Pankhurst fled to Paris, Barrett was asked to be the joint organiser of the national WSPU campaign. In 1912, despite having no journalistic background, she was put in charge of the newly formed newspaper "The Suffragette". Barrett was arrested on more than one occasion for activities linked to the suffrage movement and between 1913 and 1914 she spent time incognito avoiding re-arrest.
Document 10: Ethel Snowden: Ethel Snowden, Viscountess Snowden (born Ethel Annakin; 8 September 1881 – 22 February 1951), was a British socialist, human rights activist, and feminist politician. From a middle-class background, she became a Christian Socialist through a radical preacher and initially promoted temperance and teetotalism in the slums of Liverpool. She aligned to the Fabian Society and later the Independent Labour Party, earning an income by lecturing in Britain and abroad. Snowden was one of the leading campaigners for women's suffrage before the First World War, then founding The Women's Peace Crusade to oppose the war and call for a negotiated peace. After a visit to the Soviet Union she developed a strong criticism of its system, which made her unpopular when relayed to the left-wing in Britain.
Document 11: Charlotte Marsh: Charlotte "Charlie" Marsh (1887-1961) was a British suffragette. In 1907 she joined the Women's Social and Political Union, but did not become active as an organizer until 1908, after completing her training as a sanitary inspector. In June of that year she was imprisoned in Holloway for a month on charges of obstruction. The next year she was again imprisoned for heckling Prime Minister Asquith and became one of the first suffragette hunger strikers to be forcibly fed. During World War I she worked as a mechanic and chauffeur for Lloyd George, whilst continuing her activism.
Document 12: Edith How-Martyn: Edith How-Martyn, née How (1875, London -1954, Australia) was a British suffragette and a member of the Women's Social and Political Union (WSPU). She was arrested in 1906 for attempting to make a speech in the House of Commons. This was one of the first acts of suffragette militancy.
Document 13: Frances Nacke Noel: Frances Nacke Noel (January 5, 1873 – April 24, 1963) was a women’s labor activist and suffragette, and was known as "the most eloquent female orator of Southern California" in the early 20th century. Nacke acted as one of the primary female labor and suffrage leaders in the Los Angeles labor movement. She was one of the first "progressive activists" to tie to the suffragette movement to the labor movement, thereby achieving mutual goals of emancipation of both women and workers. Through her oration and organization, Nacke was a key contributor to the passing of the suffrage movement in Los Angeles. A large part of Nacke’s platform throughout her life was compromising the differences between class divisions in the labor movement.
Document 14: Annie Kenney: Annie Kenney (13 September 1879 – 9 July 1953) was an English working class suffragette who became a leading figure in the Women's Social and Political Union. She attracted the attention of the press and the public in 1905 when she, and Christabel Pankhurst, were imprisoned for several days for assault and obstruction, after heckling Sir Edward Grey at a Liberal rally in Manchester on the issue of votes for women. This incident is credited with inaugurating a new phase in the struggle for women's suffrage in the UK, with the adoption of militant tactics.
Document 15: Elsie Plant: Elsie Plant (1890–1982) was a suffragette, socialist and birth control activist. She lived most of her life in Stockport, seven miles from Manchester. She was an enthusiastic campaigner of the suffrage movement. Following her campaigning as a suffragette, she and her husband became key figures in Stockport's Labour Fellowship. She had three daughters: Aileen, Roma and Joyce. Aileen became a nursery school head teacher and traveller; Roma was a business woman and retail owner, and Joyce was a writer, teacher and philosopher.
ground_truth: 1905