 Critics of the mathematization of legal proof raise this point as an example of inherent limitations to the mathematical modelling of probative value (Allen and Pardo  2007a).[13]  Allen and Pardo propose an alternative, the explanatory theory of legal proof. They claim that this theory has the advantage of avoiding the reference class problem because it does not attempt to quantify probative value (Pardo 2005: 374–383; Pardo and Allen 2008: 261, 263; Pardo 2013: 600–601). Suppose a man is accused of killing his wife. Evidence is produced of his extra-marital affair. The unique probative value of the accused’s infidelity cannot be mathematically computed from statistical base rates of infidelity and uxoricides (husbands murdering wives). In assessing its probative value, the court should look instead at how strongly the evidence of infidelity supports the explanation of the material events put forward by the side adducing the evidence and how strongly it challenges the explanation offered by the opponent. For instance, the prosecution may be producing the evidence to buttress its case that the accused wanted to get rid of his wife so that he could marry his mistress, and the defence may be advancing the alternative theory that the couple was unusual in that they condoned extra-marital affairs and had never let it affect their loving relationship. How much probative value the evidence of infidelity has depends on the strength of the explanatory connections between it and the competing hypotheses, and this is not something that can be quantified.