Luigi Mangione

True, but if the prosecution seeks the death penalty (which is likely), any jurors that say they'd have difficulty condemning someone to death will be automatically disqualified with no strikes used.

Since people who don't have any problems with the death penalty is MUCH more likely to have a clear bias in favor of the prosecution and the cops are good at spotting people lying in order to get on (or off) a jury, making it a death penalty case all but eliminates any chance of a fair trial.