Chapter I. Conditions for Authority of Penalties, Sphere of Application of Penal Law et al.
Art. 10
If the Icelandic State has obtained extradition of a person from another State for the purpose of imposing a penalty, that person can only be sentenced for offences committed prior to extradition on account of which this takes place, if the foreign State has imposed such condition and the penalty cannot be ordered heavier than stipulated.
Rule of speciality
Extradition
EDIT.