I oppose the death penalty on moral principle, but even if I didn’t, there are practical problems with supporting it.
We know for certain that people in the United States are not infrequently put to death who were very probably not guilty of the crimes they were convicted of. Additionally, we know that the death penalty is handed out disproportionately to Black people. The administration of the death penalty in the United States, in other words, is racist.
So, supporting the death penalty in this specific case means supporting it in general — with all that entails for execution of the innocent and racist injustice.
That, I cannot do.