In 2016 he was selected as the Labour Party candidate for Mayor of the West Midlands but was defeated in the 2017 election by 50.4% to 49.6% of the vote in the final round.

His clients included Tony Blair while in opposition, Microsoft UK, the International Duty Free Confederation and various charities and communication companies.

[citation needed] Shortly after Gordon Brown became Prime Minister in July 2007, Simon became Vice-Chair of the Labour Party, with special responsibility to draft the "Law and Order" manifesto for the upcoming 2010 general election.

[citation needed] Following the October 2008 reshuffle, Simon was appointed Parliamentary Under-Secretary of State for Further Education in the Department for Innovation, Universities and Skills.

[citation needed] In June 2009 he became Parliamentary Under Secretary of State for Creative Industries in the Department for Culture, Media and Sport.

[2] On 5 September 2006, he and Chris Bryant co-ordinated a letter, signed by 17 Labour backbenchers, calling for Tony Blair to resign as prime minister.

[13][14] In an interview on Sky News the same day, Simon defended himself and described Cameron's attempts to reach out to the youth culture as "shallow" and "pathetic".

[16] In 2009, it was revealed that Simon had breached parliamentary rules by renting his "second home" in London from his sister, Ceri Erskine, and paying her more than £40,000 in taxpayer-funded expenses.

Simon suffers from the rare genetic disorder choroideremia: a condition that leads to progressive deterioration in eyesight, and in its later stage, blindness.

[22] Simon lives in Birmingham, is a member of the Royal Shakespeare Company, and a season ticket holder at West Bromwich Albion F.C.