With the judicial approval given to dispute resolvers at the end of last year, the English legal system is moving with uncharacteristic urgency away from the partisan, adversarial approach to litigation which has hitherto governed our processes.

In the 19th century, as commerce progressed, three problems encouraged the judiciary to appoint their own experts to assist in deciding cases before the courts. First there was the rise in numbers of people willing to give false testimony for bribes.

Second, more cases involved foreign legal rules and trade customs of which the judge might know nothing.

Third, the expansion of industry bred many cases about scientific issues involving vocabulary and ideas beyond the grasp of intelligent non-scientists.

Court-appointed experts were used in litigation about riverbeds and watercourses where the effect of physical changes had to be evaluated in the same way as building defects in Official Referees' Courts today.

Court appointment of experts is governed by three considerations. The common law principle that a judge should refrain from summoning witnesses of fact not called by the parties, the wishes of the parties themselves and the wording of RSC Order 40.

Also, an additional expert's fees are likely to be less significant in comparison with the value of the dispute where Official Referees' business is concerned and those particular courts appear better able to accommodate extended hearings.

Elsewhere recourse to court appointed expert witnesses is highly exceptional.

Where a judge is required to decide a case involving specialist knowledge he has a duty to obtain the guidance of an expert and not risk reaching a wrong decision from his own unassisted ignorance of the issues. The judge may appoint a leading specialist as an expert witness. Equally the judge may appoint the same individual to assist him not as a witness, but as a witness with no liability to cross-examination and without an extension of the trial being inevitable. The judge may appoint an assessor whose sole duty is to use his expert knowledge to enable the judge to reach a correct conclusion.

Alan Cleary is an expert witness and dispute resolver.