Sapnara was born in Sylhet District, East Pakistan (now Bangladesh) and moved to the United Kingdom as a child.
Her father, the late Mimbor Ali, was honoured by the Bangladeshi government for his significant contribution to the liberation of Bangladesh.
"[12] In June 2012, she appeared on BBC Two's Newsnight, debating against criminalisation of forced marriage with Aneeta Prem of Freedom Charity.
[14][15][16] Between 2003 and 2014, Sapnara was Chair of the Ashiana Network,[8][10] a refuge and support agency for female victims of domestic violence and forced marriage.
She was recognised for her "outstanding achievement" as the first person of British Bangladeshi origin to acquire a senior judicial position.