The family of Mark Duggan, whose shooting by police sparked riots across the UK, are to appeal for access to justice for young people.
They will be joined at a press conference by other families from Tottenham, north London, whose relatives have died after involvement with police officers.
The launch of the Tottenham Defence Campaign next Wednesday marks the 26th anniversary of the death of Cynthia Jarrett, who died after four police officers burst into her home. The incident, in 1985, led to the Broadwater Farm riots. It is also two months since the death of 29-year-old Mr Duggan.
A spokesman for the campaign said: "The campaign has been formed by local people to defend access to justice for young people amid community concerns that Tottenham will face disproportionate and unequal treatment in the wake of August's disturbances."
The families of Roger Sylvester, 30, who died in 1999 after being restrained by officers in a psychiatric hospital, and Joy Gardner, 40, who died after a struggle with police in 1993, are also to take part in the event and will speak alongside local community activist Stafford Scott.
Mr Scott said: "The police must be held to account over the death of four members of our community, for their failings to contact the family of Mark Duggan about his death and their woeful response to family members on the peaceful demonstration in August.
"Within the community, people believe the police bear ultimate culpability for the rioting that took place in Tottenham through their failure to respond to the family or to act as events unfolded. Yet it's the community of Tottenham who will be further stigmatised and punished."
He added: "We will be calling on the Government to remember the lessons learnt from the '80s, as the response that we are witnessing is almost guaranteed to further marginalise the already marginalised; this will not lessen any likelihood of future rioting it will, inevitably, increase it."
The campaign aims to ensure that anyone arrested by police in relation to the riots has access to legal advice, to inform local residents of their legal rights, and to "challenge attempts to further marginalise and criminalise the people of Tottenham".
