Lawrence inquiry
Doreen and Neville Lawrence are expected to call for the inquiry into their son's death top be reopened. (Reuters/ Luke Macgregor)

The family of murdered teenager Stephen Lawrence is expected to call for the formal inquiry into the case to be reopened after fresh claims of corruption.

Secret police documents revealed by the Independent have disclosed allegations of corruption made against one of the lead detectives investigating the 1993 murder.

The Scotland Yard police intelligence reports point the finger at lead detective John Davidson over connections with Clifford Norris, the gangster father of murderer David Norris.

David Norris, 35, was convicted of the murder along with Gary Dobson, 36, in January.

The leaked document alleges thet Davidson, who interviewed key witnesses, was involved in extensive criminal operations within a ring of corrupt detectives.

Davidson never faced charges over the allegations and has since retired to Spain on health grounds. He claimed the allegations were "devastating and false".

The Lawrence family solicitor, Imran Khan, said: "Over the last few days we have had revelations that corruption may have infected the initial investigation into the murder of Stephen Lawrence.

"The Lawrence family will now write to the Home Secretary calling for the Stephen Lawrence inquiry to be reconvened."

He claimed that the original inquiry lacked sufficient information to tackle the corruption issue at the time.

The 1999 Macpherson Inquiry concluded that there was institutional racism present in the Metropolitan Police, but concluded that there was insufficient evidence that corruption was a major impediment to the case.