Murky world of interests that peers don't declare

The Conservative Lord St John of Bletso and Labour's Lord Boateng of Akyem and Wembley (Getty Images)

A senior Conservative peer has been acting as an adviser to a European lobbying firm for five years without declaring it to Parliament, an investigation by the Bureau of Investigative Journalism and i has found.

Lord Plumb, the former president of the European Parliament, has been associated with the Brussels-based lobbyists Alber and Geiger since 2007.

But despite sitting on the Lords' EU Select Committee until May – which scrutinises draft EU law – Lord Plumb does not declare his involvement in his entry on the Lords' Register of Interests.

He is one of a number of members of the House of Lords not disclosing apparent outside interests.

On his entry in the Register of Interests, Lord Plumb lists his only remunerated employment as "farming". But he is also named as a "team member" on Alber and Geiger's website.

The peer contributed to the EU Lobbying Handbook written by Andreas Geiger and published in 2007. A year later Mr Geiger described him in an interview as a partner in the firm. But Lord Plumb said it was "misleading to regard me as being or, having been, a senior partner". He insisted he had "never been in employment, paid or unpaid" by the firm.

Detailed investigation of the interests of current members of the House of Lords suggests there is significant room for ambiguity in what is and what is not registerable.

Lord Boateng, a Labour minister under Tony Blair, and more recently the British high commissioner to South Africa, acts as international legal counsel to the consultancy DaMina Advisors, which advises firms with investments in Africa.

However, Lord Boateng does not declare his interest in DaMina. Lord Boateng said: "I am not currently required by the House rules to list my professional clients. My role with DaMina Advisors is advising them on legal and regulatory matters in relation to their African business." He added: "Any work for them is completely separate from my work in the House".

Another peer with undeclared interests is Lord St John of Bletso, who sits on the Lords Communications Committee. Last year he joined the "special advisory board" of Mooter Media, a digital media firm. He is also an adviser to the technology marketing agency Mcdonald Butler Associates. Lord St John said both positions were not remunerated but he had asked for his name to be removed from the website of McDonald Butler.