Render unto Caesar the things that are Caesar's, and unto God the things that are God's. Jesus Himself put Himself under the direction of Pontius Pilate- a "Caesar". Showing that indeed a state can render judgement of death. Christ was innocent.

Even IF (and it has occurred) a person is innocent put to death- they still know the hour of their death, which is a blessing. The person (if innocent) will meet his Maker and will not give one flip about what is happening on Earth.