[brianlweiner]

Indeed other research has indicated that lots of factors can affect a judge's decisions.

http://www.pnas.org/content/108/17/6889.full

A panel of judges would be one approach. Perhaps judges could be made aware of what the average penalty is for similar cases and that would give them an easier anchor for their decision.

[hobbyjogger]

The Danziger study assumed that the order in which the parolees appeared was random, which turned out not to be the case:

"Danziger et al. (1) concluded that meal breaks taken by Israeli parole boards influence the boards’ decisions. This conclusion depends on the order of cases being random or at least exogenous to the timing of meal breaks. . . [But] case ordering is not random ...the board tries to complete all cases from one prison before it takes a break and to start with another prison after the break. Within each session, unrepresented prisoners usually go last and are less likely to be granted parole than prisoners with attorneys...

[O]ur data indicate a success rate of 67% for prisoners with counsel and 39% for unrepresented prisoners. Excluding deferrals in the authors' data yields very similar success rates, beginning at about 75% and dropping to 42% at the end of a session. Thus, we strongly suspect that the pattern of declining success rates is a result of hearing represented prisoners first and unrepresented prisoners last."

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3198355/

[kahirsch]

Note that there is a reply to that letter: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3198336/

[mattkrause]

That paper has some serious issues.

On the practical side, the prisoners were ordered. Judges tried to break for meals after processing a whole 'batch' of prisoners from a specific prison. Within a prison block, those with lawyers went before those representing themselves, and lawyers also ordered their cases however they wanted. As you might expect, prisoners having counsel fared better than those without.

Additionally, they measured "time elapsed from a meal" in two ways: actual wall time (in hours/minutes/seconds/etc), and case order. Both measures were individually significant, but when both were put into a model, only the ordinal one remained significant. This suggests--to me, at least--that the result isn't due to a physiological process: blood sugar levels vary continuously and don't "jump" from case to case.

There was a rebuttal letter in PNAS shortly after it was published.

Edit: HobbyJogger covered most of this first. Thanks!