Sentence:  If the person slain be unknown, then in such case it belongs to the coroners to enter a <WSD>murdrum</WSD> on their rolls, according to the statute of King Knut, made on setting out for Denmark, who, for the preservation of his Danes whom he left in England, ordained that whenever an unknown man was slain all the hundred should be in the mercy of the king under a judgment of <WSD>murdrum</WSD>. Four things relieve from the judgment of <WSD>murdrum</WSD>: the first if the felon be known or the person killed; for if the felon be known then he can be attainted for the felony. The second, if the felon be taken or has fled to a church. The third, if the killing were not felonious but by misadventure. The fourth, where a man is "felo de se". Since of a man who is known no <WSD>murdrum</WSD> can be committed, it is the duty of the coroner in these felonies to inquire into the lineage of such persons who are killed, so that one may know from their kinsmen whether they were of English birth. 
Meaning of the word marked with <WSD> tags:  A secret killing, distinguished from simple homicide in that the victim and the killer are unknown.