Our feature last week on the issues of broker independence and over-riders spotlighted the simmering tensions between BIBA and Airmic, the risk managers' association.

Airmic is still concerned its members in industry and commerce are not receiving the best possible deal from brokers if those brokers are concealing the over-riders they receive from insurers. Such conflicts of interest are not what a client expects when he approaches his broker.

BIBA, on the other hand, says Airmic is being disingenuous: the practice of rewarding brokers this way for volume business is well-known, and as BIBA chief executive Mike Williams commented: "Airmic has been unable to come up with a single example of where the payments made a difference to the broker's behaviour or premium paid. It is just trying to squeeze the market."

Here, we have entered "trying to disprove a negative" territory. It is impossible for Airmic to show that a member could have received a better deal from insurer X if the broker had not been so keen to win his volume over-rider from insurer Y.

That said, BIBA's accusation of disingenuousness surely strikes home. Airmic members are highly qualified professionals, often drawn from a background in insurance and broking. They know the way the world works, and will be fully conversant with over-riders and double-dipping. If they suspect their broker of such practices, they can always ask some hard questions.

It then becomes a matter of whether they believe their broker - which is why transparency is such a crucial issue. For as David Gamble told Insurance Times this week "low levels of trust destroy relationships: transparency builds trust and helps to identify value."

No broker would argue otherwise, but it still remains the case that only Aon has yet signed up to Airmic's code of conduct, which commits it to disclosing to clients its fees and commissions. There is much cynicism amongst rival brokers about Aon's stance. But as a step towards greater honesty it cannot be faulted. So why are they alone? Until others follow suit, they are vulnerable to suggestions they have something to hide.

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