Who? Yair Cohen, 47, founding partner of London and Essex social media and internet law firm Cohen Davis.

Why is he in the news? He is the first lawyer successfully to serve a harassment injunction on an anonymous online abuser via mobile online photo-sharing and social networking service Instagram.

Injunctions are normally served in person and, because the recipient can go to jail for breaching one, the court needs to be satisfied that it has been served properly. This presents challenges to anyone serving an injunction online, particularly because when someone deletes an Instagram account, all messages that have previously been sent by that account are also deleted – leaving no proof of the online abuse.

Cohen showed the court that all images sent to the alleged offender were high resolution and so easily readable. He also persuaded the court that an instant screen-grab taken immediately after sending the injunction provided proof of service.

The case involved a London student suffering abuse on Instagram by an anonymous person posting racial and sexual abuse, and threatening to disclose private information. The online strategy worked – the abuse stopped as soon as the injunction was served.

Thoughts on the case: ‘This case shows that you can confront online trolls without having your social media account interrupted, which is good news for celebrities and others who rely on social media for their work and social life. However, serving an injunction via Instagram requires careful planning.’

Route to the case: ‘We were recommended by the client’s own solicitor as specialists in this field.’

Why become a lawyer? ‘Since my days in the army, I have been  passionate about developing practical strategies to get people out of difficult situations.’

Career high: ‘Being the first UK lawyer to obtain an injunction against [web search engine] Google back in 2011.’

Career low: ‘I was trying to remove defamatory material from a shady website when the website operator threatened to wreck my own reputation if I persisted.’