Comment by earthman on Absence of Evidence Is Evidence of Absence · 2010-07-10T23:22:33.626Z · LW · GW

In the absence of evidence for their innocence, to say that the absence of evidence for their guilt is evidence of their innocence may not be applied. If you do not have evidence for their innocence, then you DO have evidence of their guilt (by virtue of the absence of evidence being evidence of absence) and therefore you do not have the required absence of evidence for their guilt that was used to draw the initial conclusion regarding innocence.

The converse is also true.

In the absence of evidence for their guilt, to say that the absence of evidence for their innocence is evidence of their guilt may not be applied. If you do not have evidence for their guilt, then you DO have evidence of their innocence (by virtue of the absence of evidence being evidence of absence) and therefore you do not have the required absence of evidence for their innocence that was used to draw the initial conclusion regarding guilt.

You may only say that, given the presence of evidence of innocence, a lack of evidence of guilt would provide further evidence of innocence. But if you have neither evidence of guilt nor evidence of innocence, the rule may not be applied.