Delegates at the UK National Association of Pension Funds (NAPF) investment conference in Edinburgh have criticised Derek Higgs, author of the report on non-executive director practice, over the feasibility of one of his key proposals.

In a vote from the floor at the outset of Higgs's speech, 42% of delegates disagreed with his idea that non-executive directors should make up half of company boards, excluding the chairman. Only 34% agreed with the Higgs proposal.