Antonio Curatolo, a tramp...told the original trial that he had seen Knox, Sollecito and Guede together the night of the murder.

At the time Mr Curatolo recalled that he had seen "buses carrying revellers to nightclubs" on the same evening, but defence lawyers have established that all such venues were shut and there was no public transport because of a bank holiday.

The court took under advisement a request by Knox's lawyers to call another witness:

Luciano Aviello ...wrote to the original trial court three times to claim that his brother Antonio - a fugitive mobster - and an Albanian were responsible for the murder, and had given him the murder weapon and Miss Kercher's house keys to hide. Neither was ever found.

In granting the request for independent DNA analysis, the judge noted:

... the Italian penal code [provides] that a "conviction could only be secured against an accused if it was beyond all reasonable doubt".

The prosecution says it is unfazed by the ruling and the independent analysis will be a waste of time.