It is narrated from Abdur Rahman bin Bilmani that a man from among the Muslims killed a man from among the Dhimmis. When this matter was presented before the Messenger of Allah ﷺ, he ﷺ said: "I am the most entitled to fulfill my covenant." Then he ﷺ gave the order regarding him, and he (the Muslim) was killed (in retribution).
Hadith Referenceمسند الإمام الشافعي / كتاب القتل والقصاص والديات والقسامة / 1622
Hadith Takhrijاسناده ضعيف جدا، فان ابراهيم بن محمد متروك وعبد الرحمن بن البيلماني ضعيف وهو مرسل: اخرجه البيهقي: 30/8، 31- وفي المعرفة السنن والآثار لــه (4814) - وعبد الرزاق (18514) وابن ابي شيبة (27460)۔