You know how you know they are not real Christians (well one of the reasons)?

[Soph0571]

5. The death penalty is barbaric, vengeful and has no place in a civilised society...

...the religious rights vocal support for the death penalty is at direct contradiction with the core of the Christian faith

Mark 16:15
15 He said to them, “Go into all the world and preach the gospel to all creation.''

Matthew 28:19-20
19 Therefore go and make disciples of all nations, baptising them in the name of the Father and of the Son and of the Holy Spirit, ''

Matthew 10: 7-8
7 As you go, proclaim this message: ‘The kingdom of heaven has come near.’ 8 Heal the sick, raise the dead, cleanse those who have leprosy, drive out demons. Freely you have received; freely give.''

Firstly one of that suggests hang em high, secondly not sure how you do any of that if they are dead.

And as Christ said

“Judge not, that you be not judged. For with the judgement you pronounce you will be judged, and with the measure you use it will be measured to you” (Matthew 7:1–2).

SO even if you think the death penalty is not ridiculous in the 21st Century, Christians should not be anywhere near it. Real Christians that is.