When interviewed by “So What!”, James Hetfield gave his personal interpretation of the song.

Yeah. Murder One. Not many people know what Murder One is, and I’m just trying to dig deep, go around corners, and talk about him without being extremely direct. But yeah, Murder One was [Lemmy’s] rig, the name of his favorite amp. And I know he had more than one, but that’s one that stood out to me. Yeah, just paying respects to Lemmy, because without him I don’t think Metallica would be around at all, and probably [not] a lot of other bands. He was an inspiration. He was an unwavering strength, but not unapproachable. Very down to earth, very real. Had great philosophies on life. He was a lovable character, even though he looked completely menacing, he was loveable. And he’ll be greatly missed. So I thought why not celebrate him and his life in one of our songs. That’s what it means to me.