Following the Twitter conversation around last night’s Channel 4 Dispatches on phone-hacking, Andy Coulson and the News of the World, it seems that for those already following the story there was insufficient new evidence.

But for those less aware of the ongoing claims and the series of investigations that have been conducted, the programme did a great job of putting the most recent claims – sparked by the New York Times’ reports in September – into context with what has gone before, starting with Clive Goodman and Glenn Mulcaire’s arrests in 2006.

Dispatches had comments from Paul McMullen, a journalist working at the News of the World when Coulson joined, and an unidentified source who worked under former editor Coulson while he was deputy editor.

Both alleged that phone-hacking did not begin and end with Goodman and Mulcaire. McMullan told the programme that there was surprise in the newsroom following Goodman’s arrest and sentencing that no one else had been charged.

Of 13 people who worked at the paper during Coulson’s editorship or time as deputy editor and have spoken to Dispatches, not one believes that Goodman was a lone “bad apple”.

Questioning Coulson’s “collective amnesia” and rulings by the Met Police and other industry groups that Goodman and Mulcaire were the only people involved in the practice may not be new, but Dispatches did a good job of raising some new points, as yet largely uncovered by the mainstream media. In particular, the programme spoke with a non-celebrity potential victim of phone-hacking, who explained how difficult it has been to get information from the police and her mobile phone operator to check if she had been hacked.

Concerns were raised by interviewees, including Brian Paddick, who is calling for a judicial review of the Met’s 2006 inquiry, and DCMS select committee member Adam Price, who had suggested that News International’s Rebekah Brooks should be made to give evidence to its phone-hacking inquiry, that whatever the truth behind the allegations about the extend of the practice, the way in which investigations by government and the Metropolitan police have been conducted suggests that the News of the World may be “above the law”.

Tom Watson MP, who worked on the department for culture, media and sport’s select committee inquiry into allegations against the NOTW, told Dispatches that he considered giving up politics after a senior News International journalist told him that he would be pursued by its titles after he called for Tony Blair’s resignation in 2006 because of the support of News International for the then PM.

Watson has now published a letter on his website written to the Prime Minister and asking him to make a statement in parliament this week about the allegations against his communications director Coulson.

Coulson has repeatedly denied knowledge of phone-hacking at the News of the World and told Dispatches he had nothing to add in response to its broadcast.

Lack of press coverage at the time of Goodman’s arrest suggested similar goings-on at other papers, said Dispatches’ host Peter Oborne last night. But given the Daily Mail columnist’s involvement and the featured commentary from former News of the World journalists, Channel 4 and the Guardian, has last night’s broadcast created a more united front amongst the press to investigate its own state of affairs?