(Mar. 31, 2011) The Supreme Court, sitting as a panel of seven judges, has abolished a 400-year-old law that grants expert witnesses testifying in court immunity from charges of breach of duty in contract or negligence. This law was based upon public policy over concern that expert witnesses should be able to provide “testimony freely without being inhibited by the fear of being sued.” (Arthur J S Hall v Simons  UKHL 38, British and Irish Legal Information Institute (BAILII) online databases.) There were also concerns that without immunity expert witnesses would be reluctant to give evidence that is contrary to their client's interest, if this may lead the client to sue them.
The role of immunity for expert witnesses has been under scrutiny for the past several years, in particular with regard to one high-profile case in which a mother was convicted of murdering her two young children and imprisoned based on the expert testimony of a doctor that was later found to be fundamentally flawed. At that time the role of immunity for expert witnesses was considered, but the Attorney General for England and Wales expressed concern that the courts should not decide the issue of immunity of expert witnesses.
In the current case, in a majority opinion, five of the Supreme Court Justices' (two dissented) compared the role of barristers, who, since a ruling in 2000, have no immunity, to that of expert witnesses and determined that witness immunity was inconsistent with the right to a fair trial. The Justices noted that the removal of immunity for barristers has neither hindered their ability to perform their duty nor led to an increase in legal claims against them. The Justices ruled that there was no justification for continuing expert witness immunity from suit for breach of duty and that it “would be quite wrong to perpetuate the immunity of expert witnesses out of mere conjecture that they will be reluctant to perform their duty to the court if they are not immune from suit for breach of duty.” (Per Lord Phillips, Jones (Appellant) v Kaney (Respondent)  UKSC 13, ¶ 57.)
The decision does not extend to “absolute privilege from claims in defamation, nor did it undermine the longstanding immunity of other witnesses in respect of litigation.” (New Judgment: Jones v Kaney  UKSC 13, UKSC Blog (Mar. 30, 2011); Jones (Appellant) v Kaney (Respondent) supra; Expert Witness Immunity Removed, THE INDEPENDENT (Mar. 30, 2011); Expert Witness Immunity 'Wrong,' BBC NEWS (July 10, 2006); Arthur J S Hall v Simons, supra; Expert Witness Immunity Under Threat – Part I, MEDICO LEGAL website (last visited Mar. 30, 2011).)