Lewis qualified as a solicitor in 1981, and started as a prosecutor in West Midlands Prosecuting Solicitors before joining the Crown Prosecution Service at its inception in 1986 when the police prosecutorial offices were merged into a single national body.
[4] In February 2016, the CPS announced that Lewis would retire, and be replaced by Nick Folland from 16 March 2016.
[2][5] Lewis was appointed Companion of the Order of the Bath (CB) in the 2012 Birthday Honours.
[6] On 28 March 2018, he was elected Registrar to the International Criminal Court for a period of five years; and on 17 April, he was sworn in.
[9] He was appointed Knight Commander of the Order of St Michael and St George (KCMG) in the 2023 Birthday Honours for services to the International Criminal Court and international criminal justice.