The Supreme Court of NSW has revisited the UK’s Society of Construction Law Delay and Disruption Protocol. Substantively and procedurally, his Honour Mr Justice Hammerschlag’s decision in White Constructions Pty Ltd v PBS Holdings Pty Ltd  NSWSC 1166  warrants attention.
The fact that a method appears in the Protocol does not give it any standing, and the fact that a method, which is otherwise logical or rational, but does not appear in the Protocol, does not deny it standing
White’s essential complaint was that the sewer design was late, delaying the completion of the development, which in turn was said to have caused it loss and damage.
Upon a detailed analysis of contested events, the Court determined that White had not proven the breach of contract on which its case depended. With each party having led reports of construction delay experts as to when the project would have been completed and whether the default alleged delayed the whole project, the Court also addressed the competing delay cases, noting that the methods in issue had been derived from the publication of the UK Society of Construction Law’s Delay and Disruption Protocol.
White relied on an “as-planned versus as-built windows analysis”, under which “the duration of the works is broken down into windows which are framed by revised contemporaneous programmes, contemporaneously updated programmes, milestones or significant events. Key measuring points are identified on the path taken by the analyst to be critical. Changes to the critical path, critical path delays and the causes of those delays within and between each of the windows are examined to determine slippages and causes of delays.” 
PBS relied on a “collapsed as-built (or ‘but-for’) analysis”, which involved “extracting delay events from the as-built programme to provide a hypothesis of what might have happened had the delay events not occurred. This method requires the selection of “logic links” which link various components of the works to assume relationships of dependency to determine a critical path.” 
White’s expert evidence was that the project could have been completed by 15 July 2016 and that asserted delay caused a critical delay of 240 calendar days to the project. PBS’s expert evidence was that at best the works would have, in any event, not been finished before 10 February 2017 by reason of other matters, together with the opinion that at best, on a series of assumptions, the program would have been completed only 19 days earlier than it in fact was.
With its own expert assistance, the Court concluded that “… neither method is appropriate to be adopted in this case. This view is consistent with me accepting [White’s] view of [PBS] and [PBS’s] view of [White].” 
“This case demonstrates the importance of paying close attention to the actual facts rather than opinions about what the evidence establishes.” 
Stepping back from the debate on analytical method, the Court provided the salutary reminder:
“In effect … the Court should apply the common law common sense approach to causation referred to by the High Court in March v E & MH Stramare Pty Ltd (1991) 171 CLR 506. … The Court is concerned with common law notions of causation. The only appropriate method is to determine the matter by paying close attention to the facts, and assessing whether White has proved, on the probabilities, that delay in the underboring solution delayed the project as a whole and, if so, by how much.” 
Uniform Civil Procedure Rule 31.54 – assistance to court by other persons
Delay cases can be notoriously complicated, with questions of methodology sometimes casting shade upon the real issues.
So frequently in the Australian context, delay cases are conducted behind the closed doors of dispute boards, expert determination, arbitration, occasionally even a contractual cascade of all such processes. Historically, were a delay claim to find a path into the Court unhindered by the contract, a Court still might have referred the question to a technical referee.
Rather than sending the hearing out, the Court brought its own expert advisor in, noting that:
“The expert reports are complex. To the unschooled, they are impenetrable. It was apparent to me that I would need significant assistance to be put in a position to critically evaluate their opinions and conclusions.” … “I record that Mr McIntyre’s assistance was invaluable to the Court. His advice demonstrated that the complexity that has been introduced is a distraction.”
The judicial observation that rule 31.54 was “a useful rule, which is not used as often as it perhaps might (or should) be” signposts the Court’s willingness to use its available powers to cut through increasingly complex expert evidence on matters such as delay analysis.
10 September 2019
 Noting that with the decision being handed down on 6 September 2019, the time for appeal has not expired.
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