So much for the presumption of innocence

I am researching the variant approaches in different fields (medical, judicial, etc.) in determining what constitutes sufficient evidence to draw a conclusion. In that process I came across this rather disturbing piece, Burden of Proof as a Legal Fiction: One Year Later by J. Bennett Allen.

The substance of the article is anchored on the following graph. This maps three things, 1) The beyond a reasonable doubt standard, the assessed quality of evidence by jurors and judges, and 3) the conviction rates.

Yikes! Even where the evidence strongly favors the defense, 30% of the time both the judge and jury conclude that the accused is innocent. It rises to 60% conviction rate when the evidence is balanced between defense and prosecution. So much for the presumption of innocence. One has to fervently hope there is some methodological fault in the study.