Marcia has been a councillor in Lambeth since 2006 and as Deputy Cabinet Member for Customer Services helped to set-up the Customer Service Task Force to improve Council service delivery. For the Council year 2017 to 2018 Marcia was Mayor of Lambeth and nominated Carers 4 Carers (a support group for Carers) and Oasis Youth Hub (who support young victims) as her Mayoral charities.

Outside of Lambeth Council, Marcia presently manages a family centre that caters for children in need and challenging behaviour and also works as a Business Development Co-ordinator for a community organisation.