UK's Prince Harry and Meghan Markle attend memorial service for murdered black teenager

Britain's Prince Harry and his fiancee Meghan Markle arrive at a service at St Martin-in-The Fields to mark 25 years since Stephen Lawrence was killed in a racially motivated attack, in London, Britain, April 23, 2018. REUTERS/Peter Nicholls

LONDON (Reuters) - Britain's Prince Harry and his American fiancée Meghan Markle attended at memorial service on Monday to mark 25 years since the murder of black teenager Stephen Lawrence.

The service at St Martin-in-the-Fields Church, Trafalgar Square, was also attended by Prime Minister Theresa May.

Lawrence's murder in 1993 exposed racism in the London police and led to a change in the law allowing suspects to be tried twice for the same crime.

The 18-year-old student was stabbed to death at a bus stop in southeast London in an unprovoked attack by a gang of white youths shouting racist abuse.

Five men were arrested in the following months, but charges were dropped due to lack of evidence. Two of the men were later convicted of murder in 2012.

The case became a catalyst for change after exposing deep-rooted failings in London's Metropolitan Police, dominated by senior white officers in an increasingly multiracial society.

A 1999 report by senior judge William Macpherson said the murder had exposed "institutional racism" in the force and also accused officers of incompetence and a failure of leadership.

(Reporting by Guy Faulconbridge; editing by Michael Holden)