An inquiry is under way into how two day-release prisoners ended up decorating the house of former Labour Home Secretary Jacqui Smith instead of doing community work.
The men, from HMP Hewell in Redditch, were on a scheme run by a local charity, the Batchley Support Group.
A prison service spokesman said there had been "a mistake".
Ms Smith said the prisoners "didn't have anything else on" and she made a donation to the charity for their time.
Ms Smith stepped down as home secretary in June 2009 following the revelation that she had inadvertently claimed parliamentary expenses for pornographic films ordered by her husband.
She lost her seat as MP for the Worcestershire constituency of Redditch to Conservative Karen Lumley in the 2010 general election.
Phone-in
Since leaving politics, Ms Smith has worked on a number of media projects, including making a documentary on pornography for the BBC.
Source: BBC News - Prisoners painted room for ex-minister Jacqui Smith
Comment