Germany abolished the death penalty in its constitution in 1949 (founding date of [west] germany). Not because of some euro nanny human rights stuff, but because of its very special recent past. To allow the state to kill its inhabitants was seen as the first step towards killing millions of them.
The constitution of the state Hessen of which frankfurt is a part in general still allows the death penalty, however federal law supercedes that. As mentioned above deportation into states that allow the death penalty in the tried case are not allowed.