Brought up in Sheffield, Yorkshire, Johnson was educated at Ampleforth College, then at the University of Oxford, where he learnt to fly and graduated BA in maths and philosophy,[1][2] and finally at Middlesex University, where he gained a graduate diploma in law.
In 2016 he was authorised to act as a Judge of the High Court of Justice to hear cases in the Queen's Bench Division; in 2018 he was given authority to act also as a judge in the Administrative Court.
[6] In 2007, with Robin Tam QC, Johnson represented MI6 and the Foreign and Commonwealth Office at the Inquest into the death of Diana, Princess of Wales.
[7] In March 2024, sitting in the High Court with Dame Victoria Sharp, Johnson found that Julian Assange had a real prospect of success with his appeal against extradition to the United States on three of the grounds he had argued, but they adjourned the leave to appeal application to give the US government three weeks to give assurances on the three matters.
[9] In October 2024, sitting at Woolwich Crown Court, Judge Jeremy Johnson sentenced Tommy Robinson to 18 months imprisonment after Robinson pleaded guilty to two counts of Contempt of Court[10] for repeating allegations against a Jamal Hijazi[11] a Syrian immigrant.