Solicitors in England and Wales will shortly be balloted on the possibility of splitting the Law Society's twin roles of representing and regulating the profession. What would be the likely outcome in parliamentary terms if the majority recommended such a split?

It is hard to find anyone who is entirely happy with the current complaints handling system. Many MPs are not – their most frequent complaint to the Law Society is on this subject. The system, they and their constituents say, is too slow, too complicated and biased in favour of the legal profession.

The system is in the process of being reformed, the aim being to make it quicker and more efficient, and the Solicitors Complaints Bureau will soon become the Office of Supervision of Solicitors (OSS).

But whichever acronym the new body takes on, it will never be perfect. In the world of complaints handling, there are always winners and losers. And no amount of reform will ever satisfy the losers. A more drastic solution to the problem of complaints handling is to take responsibility for regulation away from the Law Society altogether. Solicitors should think carefully before agreeing to such a move. Would it really lead to an enhanced trade union role for the society, or simply to a loss of influence?

The society's strength lies largely in the fact that it is a truly professional body not just another trade union. As a body with statutory powers, it has a strong voice in Parliament and doors are opened to it which a trade union would find slammed in its face. Take away self-regulation and that might change.

For example, in the past year some government ministers have increasingly sought to marginalise the society's voice in Parliament. They have tried to do this by telling MPs that the Law Society is nothing more than a union looking after the interests of its members. That the society can counter this argument by showing it has much wider concerns is of huge benefit to the legal profession.

Take away the regulatory role of the society so it is purely trade union in function, and on any legal issue, from legal aid to family law reform, parliamentarians will reel out their stock response to unions: “Well, you would say that, wouldn't you.” Give MPs briefings which reek of nothing more than protectionist propaganda and they go straight into the bin.

These are not hypothetical points. The effects of splitting the regulatory and trade union roles can be seen in other organisations. One example frequently cited as successful is that of the British Medical association and the General Medical Council. But this may be misleading. For a start, most members of the public have no idea about the difference between the two. BMA colleagues frequently mention the large volume of complaints they receive and transfer to the GMC.

It is true that the BMA enjoys high public esteem. But the reason why its public profile has been so good is not due to the separation of the regulatory arm. Nor is it due to the fact that it can now operate openly as a trade union.

It is because the BMA seldom behaves openly as a trade union. When it has, such as during recent upheavals in the NHS, it is rarely successful. Instead, the association has chosen to concentrate on ethical and professional issues. This is the secret of its success. Rather than washing its dirty linen in public and openly debating unpalatable issues, the BMA's public face is of an organisation fronting an enlightened profession which does not put self interest above all other goals.

This has also let the BMA become a successful lobbyist behind the scenes. To be politically effective and to win over the media, professional bodies simply need two things – public esteem and respect.

If you want an example of what happens to representative bodies which act purely as trade unions, forget the BMA. Look, instead at the teachers' organisations. Since deciding to go down the trade union route they have suffered a serious loss of influence. That path spells fragmentation and loss of influence with the public, the profession, politicians and the media.

When the time comes, solicitors will have to decide whether the benefits of separating the Law Society's functions will offset its loss of influence. But they should realise the long-term consequences. Self-regulation must be got right. Must it be given away?