Abu al-Zinad reports from the jurists of Madinah that the 'aqilah (paternal kinsmen) do not bear the burden of deliberate killing, a settlement, a confession or a slave's crime; but if they wish to do so willingly, that is their choice.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الديات / 16364