[2] Kerr ran a successful secretarial agency in London, but she gave up her business to dedicate herself to working for the campaign for women's enfranchisement.

[3] In 1906, she was appointed as the paid office manager of the national headquarters of the WSPU in Clement's Inn, London,[4] on the agreement that her work would be solely administrative.

[3] On 30 April 1913, Kerr was arrested alongside Beatrice Sanders, Rachel Barrett, Agnes Lake (business manager of The Suffragette newspaper) and Flora Drummond when police raided the WSPU offices.

[6] She was sentenced to 12 months imprisonment with hard labour for conspiracy to do wilful damage to property,[7] even though she had not yet marched in a deputation or participated in any militant action.

[9] During the rearrest of Kerr and Sanders, Annie Ford, Emma Birchell and Alice Virtue tried to stop the police from taking them and were also arrested.