A new regime for the conduct of civil litigation in the UK commenced on 1 April 2013. The so-called Big Bang is likely to ring significant changes in how civil cases in England and Wales are managed.

Common law jurisdictions throughout the world are struggling to find solutions to the efficient management of civil litigation, which has become increasingly more complex and costly for participants in the process. Undoubtedly, jurisdictions such as Australia will be looking to see how the changes introduced in the UK will play out and, perhaps, some of those changes could be adopted in other common law jurisdictions.

One of the areas, however, in which the UK may be able to learn from the Australian experience, is in relation to expert evidence. This type of evidence is critical in IP cases and nowhere is this more the case than in pharmaceutical patent litigation.

The new UK civil litigation rules have made provision for the giving of expert evidence concurrently rather than sequentially as has previously been the rule. In Australia, the giving of expert evidence concurrently, a process which has colloquially come to be known as hot-tubbing, has been a feature of the Australian IP litigation context for some time. This article sets out a summary of the Australian experience in relation to the giving of concurrent expert evidence in patent cases, which may inform the way in which the new process may operate in the UK courts. In particular, it examines:

Section 76 of the Australian Evidence Act 1995 (Cth) generally rules opinion evidence as inadmissible in any proceeding. An important exception is expert opinion about a relevant issue.

An opinion is expert where it is evidence from a person who "has specialised knowledge based on the person's training, study or experience" and the opinion is "wholly or substantially based on that knowledge". An expert is therefore generally someone who due to their experience, education or training, is considered to have specialised skills, knowledge and expertise in a particular subject matter beyond that of the average person.

Expert evidence is generally used in patent oppositions before IP Australia (formerly the Australian Patent Office) and in patent litigation before the Federal Court of Australia, to provide evidence as to how the person skilled in the art would interpret the patent specification being opposed or that being enforced. Such evidence can be wholly determinative of the findings of validity and infringement, and is often crucial to the outcome of patent litigation. However, due to its importance and complexity, conveying such evidence to the court can be time-consuming. In light of the incessant need to speed up legal proceedings to reduce court resources and legal costs, a more efficient means of dealing with such evidence is desirable.

Concurrent expert evidence has rapidly gained popularity as a practical way of taking expert evidence in civil cases in Australian courts. In patent proceedings, where the construction of the patent in suit and the outcome of the case on validity and infringement will almost always come down to expert evidence, and the assistance it provides to the judge in reasoning his judgment, the means of taking such evidence is important. The means of taking such evidence may also assist the efficient use of the court's resources, leading to a reduction in legal costs for the parties.

Concurrent evidence involves, as it name suggests, experts all giving their opinion evidence at the same time. In Australia, the procedure is said to have first been developed by Justice Lockhart in the 1970s, in the joint conferencing of expert witnesses appearing before the Trade Practices Tribunal (now the Australian Competition Tribunal), in competition law matters involving expert evidence of economists about factors such as market definition. It is also a commonly used technique in international arbitration. It generally works in the following way:

There are various obligations imposed by the Federal Court of Australia Act 1976 (Cth) (FCA Act) on parties to civil litigation and their legal representatives, to conduct proceedings as quickly, inexpensively and efficiently as possible (FCA Act ss 37M(1), N(1),(2)). Similarly, the Victorian Civil Procedure Act 2010 (CPA Act) states that the overarching purpose in the determination of proceedings by the Victorian Supreme Court is the "just, efficient, timely and cost effective resolution of the real issues in dispute." (CPA Act ss 9 & 10, part 2.3 ss 16-27).

The Federal Court of Australia (FCA) Case Management Handbook (2011) also specifically states that the cost and delay of legal proceedings can be reduced by an early and continuing process of "narrowing" the issues in contest, and in relation to those issues involving no greater factual investigation than justice requires. Concurrent expert evidence is consistent with these aims and aspirations.

Rule 23.15 of the Federal Court Rules 2011 (Cth) (see www.austlii.edu.au/au/legis/cth/num_reg/fcr2011n134o2011269/s23.15.html) specifically sets out various orders of the court which can be sought by a party to a Federal Court proceeding where experts are called "to give opinion evidence about a similar question". These orders include that:

Importantly, the FCA Practice Note Expert witnesses in proceedings in the Federal Court of Australia (Practice Note CM 7 (Chief Justice Keane, 1 August 2011)), which is to be given to an expert retained by a party, explains that the overriding duty of an expert witness is to the court. The guidelines state specifically at 1.2 that "An expert witness is not an advocate for a party even when giving testimony that is necessarily evaluative rather than inferential". It is therefore vital that expert witnesses are impartial and not merely advocates for the case of the party which calls them.

To date there is no practice note in force explicitly directed towards concurrent evidence, however it is understood that such a direction is not far in the making.

An increasing number of courts and tribunals in Australia have adopted a preference for the concurrent expert evidence approach.

In Gunnerson & Anor v Henwood & Anor [2011] VSC 440, which involved a negligence action following a landslip on adjoining pieces of land, significant issues turned on the expert geotechnical opinion of consultant geotechnical engineers. More than a third of the court hearing time was said to be consumed by the experts. This increased, in the opinion of Justice Dixon, both legal expenses for each party and the resources in terms of judicial time needed to resolve the dispute. Justice Dixon had made an order pursuant to r44.06 that the experts communicate and confer with each other before trial and file a joint report. This order, he believed, met the objects of the Civil Procedure Act 2010 and additionally implemented "prudent contemporary trial management processes...". He stated "concurrent expert evidence is now the preferred process for taking expert evidence in civil cases. Its advantages will ensure its continued use. Enhanced judicial control over privately retained experts is achieved. The experience of the courts...is greater efficiency and expedition, achieved by refocussing emphasis to professional dialogue rather than cross-examination. The process allows the critical areas of disagreement between experts to be more efficiently identified and processed, both on the taking of evidence and in judicial decision making".

Despite Justice Dixon's order in this case, no joint report was in fact produced, even though the experts had met in conference. The experts expressed the lack of a facilitator as the primary reason for non-compliance. The judge criticised the parties, stating that concurrent evidence could have saved at least two days of valuable hearing time.

It is incumbent on the parties' legal advisers to properly prepare expert witnesses for the witness conclave, that now almost universally forms part of the pre-hearing preparation for a concurrent approach to expert evidence. Witnesses should have a very clear view, in advance of the conclave, on what matters are capable of being agreed and which points or matters are in debate. In the Australian experience, it is rare that nothing can be agreed. There should be no resistance by an expert to agree with a fellow expert if the matter in issue is truly non-contentious. Even a brief identification of the remaining issues in dispute, with a brief recitation of why they are in dispute, is a helpful and useful prelude to the concurrent evidence session at trial or hearing.

Expert opinion in patent litigation informs the court about the relevant technical matters, to enable legal questions such as novelty, inventive step and infringement to be decided. The factual inquiries will generally include issues regarding:

Often the party whose evidence is the most persuasive on these matters will succeed. Sometimes, particularly where the technology in dispute is complex and extensive, the parties to the dispute may prepare what is known as a "primer" document. The primer is similar to a joint report of experts, in that it is an agreed document which serves to indirectly clarify that part of the technology which is not likely to be in dispute. A primer will usually not refer to the issues in dispute, but will set out the agreed technical, contextual background information relevant to the patented technology and issues for determination by the court (see recent use of a primer document by Justice Bennett in Danisco v Novozymes (No 2) (2011) 91 IPR 209).

The use of concurrent expert evidence is well-suited to complex technical matters, for example in the fields of pharmaceuticals and information technology. One of the earliest reported Australian patent cases to employ the concurrent evidence approach in patent cases is that of Alphapharm Pty Ltd v H Lundbeck A/S [2008] FCA 559 (escitalopram) before Justice Lindgren.

In this case, the parties led evidence from a number of experts, not all of whom were cross-examined. Two of the experts conferred and produced a joint report, in which they responded to six issues that had been formulated by the lawyers for each party. In response to each issue, the experts stated the matters on which they agreed and those where they disagreed. The lawyers played no part in this. At trial, a concurrent evidence session was held where each expert was sworn in, in succession. In addition to being cross-examined in the conventional manner, Justice Lindgren asked the experts questions and the experts asked questions of each other.

More recently, in the fexofenadine patent validity case (Albany Molecular Research Inc v Alphapharm Pty Ltd [2011] FCA 120) before Justice Jessup, a number of oral concurrent sessions took place during the trial, involving several of the expert witnesses.

Another recent patent case involving concurrent evidence is Zetco Pty Ltd v Austworld Commodities Pty Ltd (No 2) [2011] FCA 848. This case concerned a claim of patent infringement and cross-claim of patent invalidity. The construction of a number of words and phrases were in issue and each party called a plumber as the person skilled in the art to give evidence. Issues about the construction/meaning of the terms "the same size" and "pipe coupling", for example, were resolved during the concurrent expert evidence, the experts unanimously agreeing what these terms meant. On the other hand, interpretations of what "valve" and "valve housing" meant was not agreed, and Justice Bennett, a strong proponent of hot-tubbing, considered what each expert interpreted the terms to mean to place the court in a position to construe the claims itself. Justice Bennett stated:

"The parties have, commendably, narrowed the issues in dispute and it is not necessary to examine in detail the different Austworld Valves [infringing articles]. A number of issues as outlined in the pleadings and in opening were resolved during the concurrent evidence of the experts called by the parties."

Her Honour then proceeded to examine the "issues presently pressed".

Most recently, Justice Middleton in Britax Childcare Pty Ltd v Infa-Secure Pty Ltd [2012] FCA 467 confirmed the positive effect of concurrent evidence stating that "the joint report and concurrent evidence at trial were successful in identifying for the court the competing arguments on the central issue in this proceeding, namely, construction".

Concurrent expert witness evidence is now so common in pharmaceutical patent cases that courts make either no comment or only passing comment about the evidence having been given this way. Present examples of pharmaceutical patent cases in which concurrent expert evidence was given are Apotex Pty Ltd v AstraZeneca AB (No 4) [2013] FCA 162 (5 March 2013) and Eli Lilly v Apotex Pty Ltd [2013] FCA 214 (15 March 2013).

It is clear from recent case law that the hot-tubbing technique can by very effective in narrowing the issues in a patent dispute. This is assuming, however, that the experts themselves have an equivalent scope of expertise to enable the joint consideration of questions and answers provided to be of any value. It is also important for those advising the parties to spend time and effort to properly and comprehensively prepare the expert, for both the witness conclave before the hearing and in respect of the concurrent evidence session itself.

In Australia, concurrent expert evidence is here to stay, and it can be confidently predicted that the take up in the UK of this approach is likely to be equally fervent. Of course, this will only occur with the support and encouragement of the judiciary and of those representing litigants.

The one factor which is likely to cement concurrent expert witness evidence into the litigation landscape is efficiency and cost saving. Hot-tubbing seems to have a long and bright future ahead of it.