But the Labour rulebook appears to make its own additional stipulations. “In opposition,” Johnson explains, “if a Labour leader resigns, the deputy automatically becomes acting leader. But in government, the rules say the cabinet – in consultation with the NEC – selects an acting leader from among their own ranks.”
That last bit could prove important. It appears to open up the possibility of a scenario in which Streeting resigns from cabinet, Starmer immediately steps down as leader, and Streeting is at that point ineligible to become prime minister – because he is no longer at the top table. Again, there is little clarity.