Ofcom today launched an investigation into Sky News, owned by Rupert Murdoch’s British Sky Broadcasting, after the channel admitted hacking the emails of criminals to generate a story.

The Office of Communications investigation came after Sky, earlier this month, admitted that it accessed the accounts of “canoe man” John Darwin and his wife Anne, along with that of a suspected paedophile.

“We stand by these actions as editorially justified and in the public interest”, insisted Sky News, as the incident emerged, adding that it was “responsible journalism” as information led to a criminal conviction.

“The Crown Prosecution Service acknowledges that there are rare occasions where it is justified for a journalist to commit an offence in the public interest. The Director of Public Prosecutions Keir Starmer told the Leveson inquiry that ‘considerable public interest weight’ is given to journalistic conduct which discloses that a criminal offence has been committed and/or concealed”, added Sky News.

“Ofcom is investigating the fairness and privacy issues raised by Sky News’ statement that it had accessed without prior authorisation private email accounts during the course of its news investigations. We will make the outcome known in due course”, said Ofcom spokesperson.

The email hacking investigation of the Ofcom is centred on Rule 8.1, which states, “Any infringement of privacy in programmes, or in connection with obtaining material included in programmes, must be warranted.”

Simon Cole, the managing editor who approved the hacking of John Darwin’s emails, is retiring after 17 years. He insisted that his decision to leave Sky News was “unrelated to the Darwin story”. Earlier this month, James Murdoch resigned as chairman of BSkyB to prevent phone hacking and other scandals at News Corp.

James Murdoch as well as his father Rupert is to appear before the Leveson Inquiry into press ethics later this week to explain their relationship with politicians.

Related: James Murdoch resignation

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