Michael Conklin (Angelo State University) has posted Reasonable Doubt Ratcheting: How Jurors Adjust the Standard of Proof to Reach a Desired Result on SSRN. Here is the abstract:

Research has already been conducted into how jurors alter the reason-able doubt standard based on different legal definitions of the standard provided and perceived harshness of punishment. This article discusses the findings of research that is the first to analyze how jurors also alter the reasonable doubt standard based on their sympathy toward the defendant — namely, how jurors “ratchet up” reasonable doubt to acquit sympathetic defendants and “ratchet down” reasonable doubt to convict unsympathetic defendants. Political affiliation and gender are also analyzed for potential causal relationships with this effect. The results of this novel re-search provide valuable information for trial attorneys, judges, and advocates of criminal justice reform.