The family of Mark Duggan, a father of four who was killed by police officers on Aug. 4, 2011, is expected to attend what's been billed as a "service of hope" on Sunday at Tottenham Town Hall in north London.
The death sparked an angry protest, which morphed into England-wide lawlessness as police failed to get a handle on the situation.
The violence embarrassed a country preparing to show off for the Olympics.
In a statement, Duggan's mother Pam said she was still seeking to know why her son died. A police watchdog investigation remains ongoing.