Whilst at Girton College, Cambridge, she joined socialist organisations including the Independent Labour Party, and went on to campaign for Women's Suffrage in Norwich.

After causing some initial controversy by not wearing a hat to Parliament, she gave her maiden speech in support of reducing the age of suffrage for women from 30 to 21, to match that of men.

[3] During the first world war, Jewson managed a centre focused on training unemployed girls up to the age of 17, and by 1916, she had joined the National Federation of Women Workers as an organiser.

[2] In 1919, she had become the secretary of that society and in this role, she attempted to act as an advocate in court, though the judge did not allow it as she had not been appointed as King's Counsel.

She explained that the hotel had "... telephones in every room, pile carpets and marble pillars everywhere [for the guests] but the servants quarters were filthy, miserable and loathsome.".

[6] She shared a mice infested room on the tenth floor with four other housemaids, and ate cold, stale, leftover food from the guests in the windowless basement.

[8] When parliament re-opened on 6 January 1924, Jewson arrived early to ensure she had a seat, but she and Bondfield caused some controversy by not wearing a hat.

While, Nancy Astor made light of the topic, Jewson was clear that the women were "not in Parliament to discuss dress or millinery, but to do something"[10] and then carried on attending without a hat.

[23] Despite a campaign over the summer of 1924, focussed on "Faith, Hope and Dorothy",[24] she lost her seat at the 1924 general election,[25] and never returned to Parliament, despite running in 1929 and 1931.

[35] She was willing to get involved at the ground level, at one point she stated she "nearly had the clothes torn off her back" due to suffrage activities, which endeared her to the crowds.