By Martin HickmanGlenn Mulcaire carried out only a dozen hacks or attempted phone hacks during Rebekah Brooks’s editorship of the News of the World, the phone hacking trial heard today.Giving evidence at the trial at the Old Bailey, detective Nicholas Oskiewicz said that of the 500-plus notes kept by Mulcaire between September 2001 and January 2003 only 12 were classified as the most serious, “Category 3”.Earlier in the trial, Det Const Oskiewicz agreed to re-examine Mulcaire’s notes after the legal team acting for Mrs Brooks’s produced their own figures which clashed with his.Mulcaire, the News of the World’s specialist phone hacker, had 11,000 pages of notes when he arrested by police in August 2006.The Metropolitan Police has combed through, and graded, every page for evidence of hacking.Det Constable Oskiewicz, attached to Operation Weeting, explained the classification system.He told the court that Category One was accorded to a note with no evidence of anything illegal – such as when Mulcaire recorded only the name of a newsworthy individual and their address.Category 2 was given to a note that indicated blagging [obtaining information by deception, such as pretending to be a hospital doctor to access GP’s records] – or was material that could be used for blagging.Category 3 was a hack or attempted hack – evidenced by the presence of a PIN for unlocking mobile phone messages; or the voicemail inbox numbers themselves, known as DDN [Direct Dial Number] or UVN [Unique Voicemail Number.]Mr Laidlaw showed the jury examples of Mulcaire’s notes from the date when he was given his first contract with the paper, 1 September 2001, and 13 January 2003, when Mrs Brooks became the editor of the Sun.For the 407 tasking by NoW news editor Greg Miskiw, there were 12 Category 3 notes, Det Const Oskiewicz agreed.Mr Laidlaw showed the jury a Miskiw-tasked Mulcaire note about the former TV presenter John Leslie and asked the police officer why he had graded that as Category 3. Det Oskiewicz replied: “The words ‘Do both mobiles’.”Mr Laidlaw repeated to the jury that it had been so graded because of the words: “Do both mobiles.”In another Category 3-graded note about the TV presenter Natalie Pinkham, Mr Laidlaw suggested to the jury that the word which the officer thought was ‘Pin’ might in fact be ‘Pink’ – and advised them to make a note to that effect.As to Neville Thurlbeck, another news editor who has pleaded guilty to plotting to hack phones, Det Const Oskiewicz said that he had classified none of his 135 taskings for the period as Category 3.Mr Laidlaw ran through 10 Category 1 and 2-graded of the Thurlbeck-tasked notes.They included a Category 1 note on the Radio 1 DJ Sara Cox, whose car registration, garage and management company had been recorded by Mulcaire.Another was a Category 2 note on the East 17 singer Brian Harvey, below which Mulcaire had written a mobile number, a name, and some financial information including the word ‘Visa’.Another of the private detective’s notebook entries was for Joanne Lees, whose boyfriend, Mr Laidlaw told the court, had been murdered while abroad.Another was about two police officers, one called Dc Stevens and another Tony Goodrodge, who had been attached to the Soham murder investigation.Finally, he showed the note for Colin Stagg, who, Mr Laidlaw pointed out, had been accused of a notorious crime, murder, and been subsequently acquitted and exonerated.As the prosecution adduced further small sections of evidence, Detective Constable Richard Fizgerald gave evidence about phone data.Detective Constable Fitzgerald told the court that the only call data relevant to Mulcaire’s hacking came from the original police inquiry into hacking in 2006, Operation Caryatid.Mobile phone companies and networks were only obliged to hold data for 12 months, the detective explained – meaning that the data only went back to 2005.He added that Mulcaire’s hacks all appeared to come from six landlines at his office in Sutton, south-west London. While the police do not have billing data for two of those, he said, the data for the others suggests that Mulcaire frequently changed his office landline number.The phones were separately operational from January 2005 to 23 May 2005; 2 February 2005 to 4 April 2005; 24 January 2006 to 16 February; and February 2006 to August 2006.Appearing for only a few minutes, the former NoW reporter Dan Evans finished his testimony.He re-asserted his statement that he had told Andy Coulson about his hacking skills at a job interview for the paper in 2004.Evans said the “body language” of another senior journalist at the meeting at a London hotel had encouraged him to raise the issue of hacking – and he mentioned that he had been able to save his then employers, the Sunday Mirror, thousands of pounds by obtaining stories so cheaply.Mrs Brooks and Mr Coulson, who edited the News of the World between 2003 and 2007, deny plotting to hack phones. The Crown is expected to wrap up its case this week.