What kind of fallacy is "Try explaining this to victim's parents"

Actually, in this latest iteration you appear to be making the case that Person # 1 is acknowledging the veracity of person # 2’s assertion of the parents’ non sequitur vis a vis their presumed emotional response. In other words, Person #1 relinquishes any of the parents’ responsibility for their presumed emotional & irrational (blaming) response, other than to say this response will be forthcoming. Person # 1 thus becomes complicit with person # 2 in acknowledging and accepting the parents’ anticipated non-sequitur fallacy (per Bo). (Of course, if Sally’s parents’ emotional response is merely one of sorrow or grief and not blaming Timmy, there is no fallacy whatsoever.)

Maybe I did not formulated my example precisely. Let's try this way:

Person 1: Timmy accidentally pushed Sally off the cliff, hence he did not committed a crime because he had no intent (and only acts committed under particular state of mind are crimes).
Person 2: Try telling that to Sally's parents!
Person 1: Sally's parents' emotions about the person who caused Sally's death are irrelevant for whether he had the intent to do it and hence - whether he is guilty for committing a crime or not.

So I am referring to a case where Person 1 is pointing out some legitimate reason for someone to be excused for hers/his actions while Person 2's counterargument against that is that the excusing circumstances are not actually excusing because the relatives of those affected wouldn't understand or agree and would want a revenge.

Let’s change Bo’s hypothetical a bit:


Person #1: The convicted-by-jury gunman, of killing 20 innocent people doesn’t deserve the death penalty, because by definition, he had to have been mentally ill (i.e., insane) to do such a thing.

Person #2 - Try telling that to the victims families.

Person #1 - are you suggesting because the victims’ families have an irrational desire for retribution based on what is clearly a highly emotionally-charged situation for them, that the gunman deserves the death penalty ?

Person #2 – Yes, except their desire is for Justice and is completely rational!

I submit this example a. preserves the OP’s postulate “Try telling that to the victims’ families” and b. avoids the non-sequitur & fallacy, by substituting a rational view, reflecting societal values, for the purely emotional (& irrational) reaction by Person #2 in Bo’s example. Thus, I think Bo is right; this postulate need not constitute a fallacy in all cases.
(Note: for clarity, it is given that the gunman was judged mentally competent while committing the act by the convicting jury.)

Sounds like special pleading to me.