McLean was born in 1985[2] and grew up in the "southern outskirts of London."[4] His father is Jamaican and worked as a retired tool maker while his mother was from Surrey and worked for United Airways.[2] He has an older brother and sister.[2]
McLean attended Kingston Grammar School, having been awarded a scholarship.[2] At a young age, he became fascinated with social issues and the criminal justice system.[2][3] In his teens, he worked for a quadriplegic who suffered from multiple sclerosis and volunteered at a hospice.[2]
After high school, McLean visited Uganda to volunteer as a hospice worker[3] at the Mulago hospital in Kampala.[5] There, he was motivated to start Justice Defenders in 2007[6] after observing that prison inmates were not given proper medical care[2][7] and seeing the conditions at Luzira Upper Prison.[8] After coming back to the United Kingdom, McLean fund-raised to provide good health facilities and educate inmates in Ugandan prisons about the law, beginning the organization.[6][9]
McLean attended the University of Nottingham, graduating in 2007.[1] He was the first in his family to earn a university degree.[4] After graduation, he moved to Kampala, where he created a team of local and international staff and volunteers with the goal of professionalizing the African Prisons Project and increasing its impact.[1]
McLean studied at the University of London by correspondence, receiving a Master of Laws in 2009 and being called to the bar of England and Wales in 2010.[1]
- UK Charity Volunteer of the Year 2006[1]
- UK Young Philanthropist of the Year 2007[1]
- Overall Winner, Beacon Prize for Philanthropy 2007[1]
- University of Nottingham Alumni of the Year 2007[1]
- UK Graduate of the Year 2007[1]
- Winner, Vodafone World of Difference Prize 2008[1]
- Fellow of the Royal Society of Arts (2008)[1]
- Ashoka Fellow[1][4]
- Time Top 30 Under 30[10]
- Grinnell College Innovator for Social Justice Prize 2020
- Qatar Foundation WISE Award 2020