McKeever and Obakin will work with the SSAC, an independent advisory body for the Department of Work and Pensions, to scrutinise and report on social security regulations.
They will also give advice on social security issues.
McKeever, who is the chair and executive director of the Northern Ireland Law Centre and director of the Ulster University’s Law Clinic, and Obakin, who is chief executive of the national charity Centrepoint, replace Les Allamby and Simon Bartley who have each served nine years on the SSAC.
Committee chair Paul Gray, said: “Grainne and Seyi are very strong successors to Les Allamby and Simon Bartley, both of whom leave the committee today having made an enormous contribution to the committee’s business over the past nine years."
Commenting on the expertise McKeever and Obakin will bring to the committee, Gray said: “Grainne will provide an important insight on developments relating to welfare reform in Northern Ireland, and Seyi will bring valuable experience relating to disadvantaged young people, especially those who are homeless.”
Four others have also been appointed. Judith Paterson joined the SSAC 1, September, Dr Jim McCormick took up his role 1, November and Rachel Badger is expected to take up her role on 1 February 2015. Existing member, Colin Godbold, will carry on for a second term of three years.