These continuous appeals to Tsarnaev's trial and death sentence are a waste of taxpayer money that accomplishes nothing but unnecessarily forcing the victims of the Boston Marathon bombing and their families to revisit their traumas. His guilt has been well established, and while jurors in the original trial may have made inappropriate statements online, it would be wrong to suggest his death penalty should be overturned because of jury bias the defense couldn't prove.
While Tsarnaev is most certainly guilty of the crimes he has been convicted of, it's not unfair for his defense team to question the role of jury bias in his trial. He has been sentenced to the harshest penalty the US has to offer, and since he has been given the death sentence, it would be wrong not to investigate the possibility of wrongdoing in the case. These checks and balances exist in the US justice system for a reason, which is why this investigation should proceed.