Grant Shapps, the spam kingpin who moonlighted as UK Tory party chairman and then an MP, sued a constituent who accused him of working for his "marketing" company after taking office.

Shapps's lawyers demanded that the constituent, a former Labour councillor, post a humiliating, grovelling retraction after he accused Schapps of misleading the public about when he stopped writing as "Michael Green" — the alter-ego used to run the business that the police called a potential "offence of fraud" and which violated Google's anti-spam guidelines.

However, the Guardian has uncovered audio of Shapps recording a sales pitch in his Michael Green persona after taking office. He has since admitted that the recording is genuine, even though he had insisted as recently as three weeks ago that he left the spam trade behind after he became an MP.

While traces of How to Corp were vanishing, Shapps continued insisting he did not use the name Michael Green while an MP. In September 2012 he told Sky's Dermot Murnaghan that "before I went in to parliament I used to write business publications and, like many authors, write under a business name". As the issue of second jobs has risen up the political agenda, the Conservative party chairman has been taken to task over his controversial past – most recently by LBC's Shelagh Fogarty who extracted three denials from Shapps that he had worked as Michael Green after 2005. A visibly annoyed Conservative party chairman – the radio programme is streamed on YouTube – brings the matter to an end by saying: "I thought the discussion here was second jobs whilst people are MPs. To be absolutely clear. I don't have a second job. And I have never had a second job whilst I being an MP. End of story."

Grant Shapps admits he had second job as 'millionaire web marketer' while MP [Randeep Ramesh/The Guardian]