Who's the most at blame here?

The trial judge, the appellate judges, the prosecutor or the defense attorney? Via Volokh, you'll see totally absurd events unfold:

Here’s what happened in the middle of a trial of parents for killing their child through child abuse (felony murder under Georgia law):

[T]he prosecutor, in the final moments of her concluding argument on behalf of
the State, “clicked” her fingers at which signal one of the deputies in the
courtroom turned out the lights and an associate prosecutor “popped out a cake
out of a grocery bag” complete with eight candles, which were then lit with a
lighter brought into the courtroom; the prosecutor and her associate then
proceeded to sing to “dear Josef,” i.e., the deceased victim, the celebratory
words to “Happy Birthday.”

The dissent (in Smith v. State, decided Monday by the Georgia Supreme Court) argued that this was prosecutorial misconduct that required reversing the convictions, even though the defense lawyer did not object:

There was no legitimate reason for what the prosecutor did. It was neither
argument nor rebuttal, because there is nothing at all in the record about
birthdays and birthday cakes to raise even the slightest possibility that the
prosecutor was drawing a reasonable inference from the evidence presented or the arguments made by defense counsel. To the contrary, the evidence established that the victim’s family followed an austere lifestyle, including dietary
restrictions, that eliminated the possibility of the victim experiencing the
type of birthday event dramatized by the prosecutor. The prosecutor’s birthday
production was not meant to be argument or rebuttal: it was a theatrical stunt
spun out of pure fantasy. Its sole purpose was to prejudice the rights of
appellants before the jury in an impermissible attempt to invoke the jury’s
passions and divert the jury from the evidence. It offended the dignity and
decorum of the court and violated every precept of professionalism and fair
play. Yet the trial court did absolutely nothing. The event played itself out
without the trial judge performing his duty to maintain decorum in the
courtroom. Moreover, after observing this “‘preposterous’” performance, the
trial court took no steps of any kind to minimize the prejudice. There was no
rebuke to counsel; there was no direction to the jury to ignore the spectacle
they had just witnessed; there was no charge to the jury that sympathy for the
victim was to play no role in their verdict.

[Footnote: I am giving the prosecutor the benefit of the doubt by concluding that her motive for pulling this stunt was simply to evoke sympathy for the victim in an unprofessional attempt to obtain guilty verdicts at any cost, as this motive is less offensive than the other possible motive raised by this case, i.e., that she was
deliberately pandering to the television audience observing the proceedings on
Court TV. See defense counsel’s testimony at the hearing on appellants’ motion
for new trial (“I understand the cameras were rolling and everybody wants to be
Nancy Grace’s friend”).]

The majority agreed the prosecutor’s behavior was improper, but concluded that the defense lawyer’s decision not to object was a strategic judgment, and therefore not grounds for reversal. (“Arora testified at the motion for new trial hearing that he made a strategic decision not to object to the ‘Happy Birthday’ song during closing argument. Specifically, Arora thought that the ‘Happy Brithday’ song was so ‘preposterous,’ ‘absurd,’ and ‘over the top’ that ‘it would turn the jurors off,’ and that he should not call any more attention to it by objecting to it.”)

HT: MC