Gordon Brown, who was in Number 10 from 2007 to 2010, went to Kirkcaldy High School - now a comprehensive in Fife.
Mr Brown was reportedly taught in a special fast stream while at the school..
Theresa May attended Holton Park Girls' Grammar School, which was initially a state school that became Wheatley Park Comprehensive School while she was a pupil.
The government website even states that she attended "both grammar school and comprehensive school" in its official biography on May.
Questioned about the other leaders who went to state schools, Ms Truss’s press secretary said: “My understanding is this is quite complicated and it changed halfway through and comps weren’t actually called comps until the 60s or something like that.
“I’m not going to do a pop quiz on former PMs’ schooling.”
Others also pointed out that John Major, Theresa May, Lloyd George, Harold Wilson, Edward Heath, James Callaghan, and even Margaret Thatcher all went to non-fee paying schools.
\u201cLiz Truss says she is "the first prime minister of our country to have gone to a comprehensive school." \n\nBoth Gordon Brown and Theresa May went to comprehensive schools.\u201d
\u201cTruss says she's the first PM from a comprehensive school.\n\nIsn't Kirkcaldy High where Brown went a comp?\n\nCallaghan's was a secondary modern.\n\nWilson, Heath & May(after 11) also state educated.\n\nRamsay MacDonald left school at 15.\u201d
\u201cLiz Truss says she's proud to be the first UK PM to go to a comprehensive school but of course that doesn't make her the first PM to have been to a state school. Brown, Major, Thatcher, Heath, Wilson and Lloyd George all "state" educated.\u201d
The speech was interrupted by fracking protestors who shouted “who voted for fracking?” as the prime minister vowed to “get Britain moving” in her make-or-break speech to the Conservative Party conference.
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