Convicted murderers often get lighter sentences

If it was my wife, I'd probably do my best to save her.

Therefore the sentence seems unusually harsh in comparison with the lenience in other equivalent cases.

And if the allegations about this being pre-planned (e.g., paragraphs 20 and 21 of the indictment) were supported by enough evidence to persuade the jury (and the jury was persuaded), then it's hard to see how they have a good chance of getting this overturned on appeal. Because unless I greatly misunderstand the law, in jury trials, as opposed to ones where the judge is the one making a ruling, appeal courts don't go over the evidence anew unless actually new evidence has turned up in the meantime (they don't "relitigate the facts", as I've seen it put in civil cases); instead, appeal courts assume that the evidence presented was factual, and what they do is look at the points of law that were used. Was the law properly applied? Were there mitigating circumstances that the judge didn't allow to be presented even though he should have?

And the law on things like attempted murder, or knowingly trying to conceal evidence when you know it's going to be used in a criminal case, is pretty clear-cut; there's not much room I can see for expecting the convictions to be overturned on a point of law. Not unless new evidence turns up that wasn't presented at the trial.

(EDIT to add: Actually, I believe that even in civil cases where a judge has made the ruling rather than the jury, appeal courts don't re-litigate the facts. Just as with criminal cases, in civil cases the judge will say "Hey, if you had evidence to present against that allegation, you had your chance to present it at the first trial." Only if the evidence is truly new, or the guy trying to present it truly didn't know it at the time of the first trial (and had no reasonable way of knowing it), does the appeal court say "Okay, we'll re-examine the facts in light of this new evidence." Otherwise they say "Re-litigating the facts is not our job," and unless the guy can show that the judge did something wrong (such as throwing out evidence that by law he should not have thrown out), then the appeal court won't look at new evidence. They only look at whether the law was actually followed correctly in the courtroom.)

My source for that knowledge, BTW, is a blogger (now deceased) whom I used to read regularly; I'll call him Mr. Smith. He wrote some unflattering things about someone else whom I'll call Mr. Jones, saying things like "Mr. Jones was once convicted of perjury, so you can't trust anything he says." Mr. Jones sued Mr. Smith for defamation. Mr. Smith put every legal filing, both Mr. Jones's complaint and his own defense, on his blog (legal filings, unless sealed by the court, are public domain under U.S. law as I understand it). By reading those filings, as well as the judge's decisions (also public domain under U.S. law), I actually learned quite a bit about how the U.S. legal system works. Including how appeal courts work, because when Mr. Jones appealed his lost lawsuit (Mr. Smith won his case, because Mr. Jones really had been convicted of perjury some thirty years back, sometime in the 1970s or 1980s, and under US law truth is an absolute defense against defamation — which is not the case in all countries, but is the case in the US), Mr. Jones tried to introduce evidence in the appeal and the court said "Nope, you knew about that at the time of the first trial, so you should have presented it then" and refused to consider the new allegations that Jones was presenting.