3.5.3 Reasonable hypothesis (RH) cases

The RH test applies to liability claims relating to warlike and non-warlike service.  In order to accept the claim the person must present a 'reasonable hypothesis' in the form of contention X (due to warlike/non-warlike service) caused or aggravated condition Y (injury, disease or death).

Prior to the establishment of the SOP regime, questions about what constitutes a 'reasonable' hypothesis had been established in the case law.  The Full Federal Court in Repatriation Commission v Deledio [1998] FCA 391 articulated the steps a decision maker must take in order to properly apply the law when making a liability determination where the RH standard of proof applies.

These steps placed the SOP regime within the existing case law, in particular the High Court decision in Byrnes v Repatriation Commission [1993] HCA 51 which had endorsed the earlier High Court decision in Bushell [1992] HCA 47.

In Bushell the High Court found that it would be rare for a hypothesis not to be reasonable if supported by a relevant medical expert.  In Byrnes the High Court articulated a 2-step process to determining RH claims:

• Does the material point to facts that (if true) raise a reasonable hypothesis connecting the claimed injury, disease or death with the person's service?
• The claim must succeed if such a reasonable hypothesis is raised, unless the raised facts are disproved beyond reasonable doubt;  or facts inconsistent with the hypothesis are proved beyond reasonable doubt.

The Bushell-Byrnes approach continues to apply within the Deledio context;  and in its own right to determinations involving non-SOP conditions.

Following the Deledio decision, the Repatriation Commission issued guidelines – CM 5017:  application of s120 VEA following the FFC decision in Deledio – which also apply to MRCA delegates.

The Deledio steps – as modified by the Full Federal Court in Bull v Repatriation Commission [2001] FCA 1832 – are described below.

Step 1:raising a hypothesis

This is the point where a person hypothesises a causal connection between the claimed condition and the circumstances of their service.

The material presented must raise facts, which, if true, would connect the person's warlike or non-warlike service with the claimed condition.  It does not matter whether or not the contention is consistent with SOP factors (if the condition is covered by a SOP) as this will be investigated later.

There is no fact finding at this stage, however, the raised hypothesis must be pointed to by the material, not merely a possibility left open by an absence of evidence.  While the hypothesis may assume the occurrence or existence of some fact, it must be consistent with known facts, commonsense and experience and cannot be too tenuous or remote, as explained in East v Repatriation Commission [1986] FCA 242.

An example of a reasonably assumed fact would be a contention that an injury on service caused spondylosis later in life:  the injury can be assumed unless disproved by other known facts.

If no hypothesis arises in the process of considering all of the material, or if a fact on which a hypothesis is based is absent or known to be untrue, then the reasonable hypothesis pathway is closed as there is no connection with the person's warlike or non-warlike service.

However, where the person also has peacetime service that pathway remains open and the claim must then be considered under that paradigm.

Step 2:  identifying the relevant SOP (as modified by Bull)

Once a hypothesis has been raised, the decision maker must then decide whether or not the condition diagnosed and for which liability is being claimed is covered by an RMA SOP Instrument.

If the condition is the subject of a SOP, then the current instrument applies.  There are no accrual rights under s341 of the MRCA:  the SOP in place at the date of determination (for primary and/or review decisions) must be applied.

The decision in Bull confirmed that if there was no SOP for the condition claimed (and diagnosed) then the Bushell-Byrnes approach prevails.

Note:  The Deledio judgement contained obiter dictum comment that if there was no relevant SOP the claim would fail.  This is not so – for non-SOP determinations, the legal authority is the Full Federal Court decision in Repatriation Commission v Bey [1997] FCA 1347 which reaffirms and explains the operation of East in the light of the Bushell-Byrnes HCA decisions.

The following step 3 does not apply to non-SOP determinations – proceed to Step 4 if the condition claimed is not covered by a current RMA SOP.

Step 3:  applying the SOP factor template

If the condition claimed is covered by a SOP the question now arises as to whether or not the hypothesis is 'reasonable'.  The hypothesis can only be judged as such if it fits the template of the relevant SOP.

The hypothesis raised by all of the material must meet one (or more) of the SOP factors.  Every element of that factor – including RMA definitions of words and phrases – must be consistent with the raised facts:  Howard v Repatriation Commission [1999] FCA 1030.

Where the hypothesis of raised facts does not support all of the elements required by the SOP factor, the hypothesis cannot be 'reasonable' and the claim must fail.

Step 4:  final test (Deledio)

It is only at this stage that the decision maker must find facts from all of the material.  In so doing, no question of the onus of proof or the application of any presumption will be involved.

This includes the question of whether the raised hypothesis is 'reasonable':  an application for special leave to appeal to the High Court – Owens  v Repatriation Commission [1996] – was dismissed on the grounds that whether or not a hypothesis is 'reasonable' is a finding of 'fact'.  The application was heard by Brennan CJ in relation to the decision in Owens  v Repatriation Commission [1995] 38 ALD 481.

For SOP conditions, the hypothesis will be reasonable if it meets one or more of the factors prescribed in the SOP template.  For non-SOP conditions the hypothesis will be reasonable if it is supported by medical opinion.

Having established the 'fact' that the hypothesis is a 'reasonable hypothesis', delegates must follow the High Court decision in Byrnes.  Hence, the claim must succeed, unless satisfied beyond reasonable doubt that the kind of injury, disease or death was not contributed to by the person's warlike or non-warlike service.