A Green party candidate and his mother have been arrested on suspicion of stalking their local Conservative MP. Chris Hallam, 48, and his mother, Christine, 76, former teachers from Buxton in Derbyshire, were arrested in September after Robert Largan, the MP for High Peak, accused them of harassing and stalking him. They are now on bail and are banned from going within 50 metres of him and three members of his staff and within five metres of his office. Chris Hallam stood for the Green party in the High Peak borough council elections in May and was beaten by one Labour party candidate and another from the Conservative party. He is also High Peak’s Green party campaign coordinator, and he claims he cannot carry out his duties because of the stringent bail conditions imposed after his arrest. The Hallams say their only crime was turning up to all of Largan’s constituency events after the MP blocked them on Facebook, and asking questions about local and national issues. Largan reported the Hallams to the police in September after sending them a “cease and desist” letter on 7 July, which informed them that “your persistent actions over the last three months, including but not limited to attending constituency surgeries around High Peak after being specifically asked not to attend in person, and disrupting the surgeries by your aggressive behaviour, are unacceptable.” The letter said the behaviour had continued “despite advice from Derbyshire police that you should not attend my surgeries in person”. Ordering them to stop “all such activities” immediately, Largan wrote: “I believe your behaviour has caused harassment, alarm and distress to myself and my staff on a number of occasions.” Warning them that he may contact the police if they ignored the letter, he said they could raise issues with him regarding constituency matters only by writing a letter or emailing him. Hallam admits that he and his mother ignored the letter and turned up to see Largan at a branch of Morrison’s supermarket in September. On arrival, he said, two police community support officers (PCSOs), as well as Morrison’s security guards, prevented them from speaking to the MP. He said he then tried to attend another surgery on 15 September held outside Largan’s office in Whaley Bridge, which ended up being cancelled “due to security reasons”, according to a sign on the door, which Hallam posted to social media. Hallam said he was arrested a few days later, on 19 September, and put in a police cell and interviewed for three hours before being bailed. In response, his mother decided to go to see Largan herself, posting on social media that she planned to attend a surgery in the town of New Mills. “She was going to ask him a few questions about what’s gone on,” said Hallam. The following morning she, too, was arrested on suspicion of harassing Largan, and was bailed with the same conditions. They are suspected of stalking the MP, including by filming him, following him to his car and “screaming and shouting” at him and his staff during surgeries, driving other constituents away. Hallam accepts he used to covertly make audio recordings of their meetings, which he would summarise on his Facebook page, and once openly recorded a meeting using a GoPro bodycam. Hallam told the Guardian that he planned to sue Largan on the basis of discrimination based on political belief. “Because my mother and I are from parties different from him and because he’s clearly doing it because our politics don’t align with his,” he said. He argues he has committed no crime, and while he waits to hear whether he will be charged he wants the bail conditions removed so that he can carry out his Green party campaign work. “As the campaign coordinator of the High Peak Green party there are many events that I have to attend which he attends and to restrict my attendance will detract massively from the local democratic process as a result,” Hallam said. A spokesperson from Largan’s office said: “Constituents of all political persuasions are welcome at Mr Largan’s weekly help and advice surgeries. Indeed, Green party councillors have attended Mr Largan’s surgeries and are welcome to do so at any time. “Since being elected, Mr Largan has been proud to go the extra mile for his constituents, taking up over 50,000 individual cases on behalf of local people and continuing to do weekly help and advice surgeries, without appointments being necessary, even in the immediate aftermath of the murder of Sir David Amess, against the expressed advice of security. “This regrettable case has nothing to do with party politics and is entirely about an unpleasant and sustained campaign of harassment.” The Green party declined to comment. Derbyshire police said: “The force has arrested a man in his 40s and a woman in her 70s in relation to an allegation of stalking. The pair have been released on police bail while inquiries continue.”