The Los Angeles Times has letters to the editor reacting to the October 29 op-eds, noted here.  They include yours truly reacting to Jimmy Carter's article and Gil Garcetti reacting to James Ardaiz's article.

Garcetti claims, "The National Research Council found in April that capital punishment has had no demonstrable effect on murder rates over the last 30 years."  This statement is cleverly worded to mislead people into thinking the report concludes that deterrence has been disproved.  In fact, the report said the evidence does not prove the case either way because these kinds of studies are not capable of definitive proof.  This is a hugely important difference that most people would not pick up from the word "demonstrable" but which allows Garcetti to claim that his statement is not literally false.  In addition, the report plainly states right up front that the conclusions are only those of the individual authors.