Lawyers for the family of Stephen Lawrence are due to make opening statements to the public inquiry into undercover policing on Tuesday.

The campaign for justice for the murdered teenager, who was killed by a gang of racists in Eltham in 1993, was infiltrated by an undercover Metropolitan Police officer.

Using the fake name David Hagan, the officer, referred to in the inquiry as HN81, joined Movement for Justice in the late 1990s and remained a member for two or three years.

This included during the Macpherson public inquiry into Stephen's murder and the racism, alleged corruption and incompetence that dogged the police investigation into his death.

HN81 met acting detective inspector Richard Walton, who was working on Scotland Yard's final submissions to the probe, and passed on information including that Stephen's parents had separated.

In 2014 a report on undercover policing by barrister Mark Ellison QC alleged that Mr Walton "obtained information pertaining to the Lawrence family and their supporters, potentially undermining the inquiry and public confidence".

On Tuesday lawyers for Stephen's mother, Baroness Doreen Lawrence, and his father Dr Neville Lawrence, are expected to make opening statements to the inquiry.

A statement is also due to be made on behalf of Michael Mansfield QC, who represented the family for several years.