Sussex Police are re-examining an unsolved double murder in the light of Government plans to change the law.

Ministers plan to scrap the double jeopardy rule, which prevents anyone being tried twice for the same offence.

Russell Bishop was cleared of strangling nine-year-old playmates Karen Hadaway and Nicola Fellows in Brighton in 1986 and no one has been convicted of the crimes.

Bishop is serving life for the 1990 kidnap and attempted murder of a seven-year-old girl from Whitehawk, Brighton, and he could make his first bid for parole in just over a year's time.

Plans announced in the Queen's Speech this week to scrap double jeopardy mean suspects could be tried a second time for the same crime if significant new evidence is uncovered.

The new law would be retrospective and Detective Superintendent Kevin Moore, in charge of cold-case reviews, confirmed the force was looking again at the double killings in Wild Park, Moulsecoomb, dubbed the Babes in the Woods murders.

He said evidence and exhibits from the investigation were being studied but he declined to go into detail.

The mothers of both victims welcomed the moves.

Susan Eisman, Nicola's mother, said: "It has given us hope and encouragement.

"Not a day goes by without me thinking of Nicola and I will not rest until justice is done."

Michelle Johnson, Karen's mother, said: "I want the right person to be locked away. This is a welcome move forward but I don't intend building up my hopes - I have had too many dashed in the past."

Any new examination of the evidence in the Wild Park case could well focus on a Pinto sweatshirt which was linked to the murdered girls by forensic science tests.

Bishop's girlfriend at the time, Jenny Johnson, told police it belonged to Bishop but testified in court she made the statement under duress.

DNA testing was unavailable at the time.

Meanwhile, the families of both murdered girls were today visiting Downing Street to step up their campaign for harsher penalties for paedophiles.

They want child abusers and killers to serve their entire sentences, including life, unless they undergo therapy and prove they no longer pose a risk.

Mrs Eismann, 52, will hand in a 40,000-name petition to Prime Minister Tony Blair's office.