A headteacher is to be paid £10,000 in a landmark legal case after accusing two parents of harassment.

Kevin Flanagan claimed damages of £20,000 from Keith and Stephanie Critchley, whose children used to attend Pensby High School, on the Wirral, Merseyside, and also sought an injunction constraining their behaviour.

The case was due to go to the High Court later this year, but a settlement has now been reached. According to Mr Flanagan’s legal representatives Brabners LLP, this has resulted in a court order that the Critchley’s pay £10,000 in costs and damages and observe multiple restraining and non-harassment orders.

Brabners said the order also meant that the couple “must take down any offending online accounts and petitions concerning Mr Flanagan”.

It added that the couple was restricted from entering school property, approaching the school, physically approaching or following Mr Flanagan and his family, or being in close proximity to his home. If they failed to comply, the Critchley’s risk being held in contempt of court and potential prison sentences being imposed.

The legal claim was supported by the school’s governors, it was previously reported, and estimated legal costs could also have risen to more than £577,000 if it had gone to the High Court. The school agreed to pay Mr Flanagan’s costs, but the size of the bill would have depended on the outcome of the legal action.

In a statement following news of the settlement, Mr Flanagan said: “The last near-two years have been a hugely upsetting and traumatic period – not only for myself but my family, colleagues and the broader school community.

“I would like to thank them for their support at a time when my integrity and leadership have been unfairly brought into question in a very public attempt to undermine my position and the school’s important work. Legal proceedings were always the option of last resort and they followed strenuous efforts by the school governors to seek to end the harassment.

“They were an unfortunate outcome of a lack of support or meaningful intervention from the police and other relevant parties including, regrettably, the local authority. I’m pleased we have ultimately been able to bring the matter to a positive conclusion – ending a campaign of appalling behaviour that went well beyond what was reasonable, encouraged others to make vexatious complaints, and ultimately distracted us from the critical task of educating students.”

The Critchleys previously told the Liverpool Echo: “We strongly deny the allegations of harassment and assert that we have acted reasonably, transparently, and lawfully throughout. We emphasise that our duty of care to our daughters, Kayti and Leigha, has been the driving force behind our actions.”

Nick McAleenan, partner and harassment law specialist at Brabners, said: “Teachers are increasingly being subjected to anti-social behaviour at the hands of parents and other individuals. The conduct exhibited by the Critchleys is sadly something hard-working teachers up and down the country will be all too familiar with.

“Clearly, discourse and legitimate challenge are an integral part of our society, but it’s vital that teachers and school leaders are afforded far greater protections – be that from the police or the education system itself – in order to carry out their work safely and free from harassment. It’s my hope that Mr Flanagan’s successful claim acts as a watershed moment in tackling unwarranted disruption of schools and the education of young people.”

A spokesperson for Merseyside Police said: “We are aware of a long running dispute involving the two parties and we have investigated a number of allegations and counter-allegations.

“There is no evidence of any criminal offences being disclosed or any course of conduct taking place which would amount to a criminal offence.” The force added it previously gave advice to Mr Flanagan “about trying to avoid the other party and how to contact police if he felt that his safety was in danger, or he had been the victim of a crime”.

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