I'm a little surprised at the "trials shouldn't be decided on probabilities anyway" arguments. It's not as if all available data is plugged into an obscure equation and if the result is > 50% guilty, you get convicted.
As it is applied, like in the example case in the article, it's to judge the legitimacy of forensic evidence. Of course we don't have the numbers here, but it's possible that there is a comparatively high probability that someone else than the defendant might have left the same shoeprints, given the abundance of that shoe profile. This is in my opinion a completely valid way to cast reasonable doubt on this kind of evidence.
Now, such arguments are usually only used when there is a notably high probability involved, and I doubt that Nike's sales figures are that inaccurate to distort the result by whole magnitudes. Also, I don't think the consulted expert took Nike's sales figures for granted and immediately went to calculating - there are methods to deal with the insecurity here as well.
As it is applied, like in the example case in the article, it's to judge the legitimacy of forensic evidence. Of course we don't have the numbers here, but it's possible that there is a comparatively high probability that someone else than the defendant might have left the same shoeprints, given the abundance of that shoe profile. This is in my opinion a completely valid way to cast reasonable doubt on this kind of evidence.
Now, such arguments are usually only used when there is a notably high probability involved, and I doubt that Nike's sales figures are that inaccurate to distort the result by whole magnitudes. Also, I don't think the consulted expert took Nike's sales figures for granted and immediately went to calculating - there are methods to deal with the insecurity here as well.