Several individuals in the industry have argued to PRWeek that the PRCA's approach to peers was "inconsistent", with another telling PRWeek that the wording of those rules needed to change.
PRCA director-general Francis Ingham last week told the Mail on Sunday that it was "disgraceful and unethical" for MPs to work for lobbying firms, and told PRWeek there was "growing disgust" towards those who did.
The PRCA's Public Affairs and Lobbying Code of Conduct, part of its Professional Charter, says: "Members conducting public affairs and lobbying services must not... employ any MP, MEP sitting peer or any member of the Scottish Parliament or the National Assembly of Wales or the Northern Ireland Assembly or the Greater London Authority", or "make any award or payment in money" to them.
Among the PRCA members that employ peers and are active in public affairs are Edelman UK – its board is chaired by financial sector veteran Lord Myners, and includes former BP group chief executive Lord Browne. Another is Instinctif Partners, which employs Baroness Rock.
However, Ingham told PRWeek: "Edelman and Instinctif are absolutely compliant with the PRCA Professional Charter and Codes of Conduct, and always have been."
Warwick Smith, who leads Instinctif's global public policy practice, told PRWeek: "Baroness Rock acts as a business adviser principally to [CEO] Richard Nichols... For obvious reasons, her activities and remuneration are deliberately wholly separate from the activities of my team."
Previous examples include Lord Bell, who chaired the now-defunct Bell Pottinger. Elsewhere, current PRCA member Tulchan employs Lord Feldman, although it is not affected by the rule above, as it does not carry out any public-affairs work.
Tulchan founder Andrew Grant said the firm's contract with Feldman was in line with PRCA guidance. "It is stipulated that he will never conduct lobbying and we will never ask him to, for any of our clients," he said.
Asked about the rule of not employing peers, Grant said: "The guidance has to be changed or the language [of the rules] has to be changed."
Nicholas Dunn-McAfee, head of public affairs at the PRCA, said: "There are a small number of peers who are members and fellows of the PRCA and who occupy leadership and management positions in various forms. Like all industries in the UK, there are a selection of people at the top who have been honoured for their contribution to public life in some way, shape, or form.
"There is one point in our Codes of Conduct where peers are mentioned, but there clearly exists a distinction in the real-world application of that Code between full-time, salaried politicians, and those who have been given an honour for public service and distinction. There is also a distinction between those that are paid to undertake lobbying activities, and those who help to run major companies.
"If there is any confusion within the industry around this distinction, we will happily work with our members to explain further."
Edelman and Instinctif are also members of the Association of Professional Political Consultants (APPC), whose code of conduct contains the same rule. However, its rules also state that members are not in breach of the code if another part of their business employs the MP, MEP or peer.
Its chair, Paul Bristow, told PRWeek: "It is APPC policy that members of the House of Lords are not allowed to conduct UK public affairs or lobbying work for a member agency. It's vital there is never any conflict between the role of a legislator and [any] involvement they may have with any public affairs organisations. It's a core tenet of APPC membership."
A number of agencies outside of PRCA or APPC membership have relationships with peers. Alongside those mentioned in the recent Mail on Sunday piece – which includes former Cameron adviser Baroness Fall's job at Brunswick – there is Lord Gilbert of Panteg, who lists Finsbury as a client of his personal consultancy.
Elsewhere, Baroness Wheatcroft was previously an adviser to Bell Pottinger, while Lord Stevenson is a "passive shareholder" with a four per cent stake in Lexington Communications, according to his parliamentary biography.
- This story was updated on 26 October with additional comments from Ingham