City solicitors are being asked to dig deep into their pockets in support of the human rights organisation Liberty.
Michael Skrein, from Richards Butler, and Maggie Rae, from Mishcon de Reya, have initiated a campaign to raise funds for the organisation's legal department.
The two partners, who were involved in setting up the City Firms Pro Bono Panel, have written to almost 100 City solicitors asking for contributions.
Liberty's legal department and the pro bono panel take up test cases challenging abuses of human rights in the UK and in Strasbourg.
The organisation receives up to 100 letters a week asking for help and needs more staff. It hopes the new initiative will raise £30,000 a year to allow it to employ a third qualified legal officer.
John Wadham, solicitor and director of the organisation, said: "Liberty has taken a wide range of cases in this country. These include challenging government proposals for secure training centres for children, the growing use of public interest immunity certificates and the use of bugging devices by the police."