I like this new legal test that the frum world seems to have adopted. We can call it the Rubashkin/Grossman rule. Under this rule, no Orthodox Jew can be penalized for crimes as long as there is any non-Jew who received a lesser sentence for similar crimes. So if someone in New York stole $300m and got 22 years, then a Jew who stole $247m in North Dakota cannot receive a sentence of greater than 22 years.
Also, any non-Jew who commits a crime will need to be sentenced to a harsher penalty than whatever penalty a Jew who committed an analogous crime received. Nowadays, the most recent Jewish murderer has been Martin Grossman. So any non-Jew who kills, must receive the death penalty.
FWIW, I don’t have any interest in seeing Dzokhar get the death penalty. What will it do for me? It won’t bring back the people who died, or heal the wounded. If you care about the victims, make a donation to them; it will help a lot more than railing about the death penalty on Facebook. The impulse for revenge is a childish one, and should not be encouraged.