A junior doctor who claims his career was ruined for whistleblowing on the NHS has won what could prove a landmark legal victory in the fight for protections for young medics who raise concerns in the workplace.

Judges at the Court of Appeal said a new interpretation of employment law legislation was needed to "maximise the protection" for the NHS's 54,000 junior doctors.

The judgment upheld the appeal of Dr Chris Day, who raised £140,000 through crowdfunding to fight the case, against the Government agency Health Education England (HEE) for a new employment tribunal.

The three judges challenged the ruling of an earlier tribunal that said Parliament had deliberately excluded junior doctors' relationship with the education and training body from protection under employment law.

Dr Chris Day raised £140,000 through crowdfunding to fight the case. Credit: ITV News

Reacting to the judgment, Dr Day said: "I hope this victory encourages junior doctors at a time when they have been let down by so many people in positions of power.

"This decision is good for patients, doctors and culture in the NHS. I am also pleased the case has assisted agency workers in other industries."

He added: "I want to acknowledge and thank our 4,000 plus supporters that donated over £140k."

Dr Day claims his career was destroyed after he raised concerns over staffing levels at a hospital in south-east London.

Dr Chris Day had raised concerns over understaffing. Credit: ITV News

He reported he had been forced to cover extra wards, including A&E, after two locum doctors failed to turn up and alleges his career was stopped short because he had spoken out.

Dr Day, who failed to find permanent work after a one-year placement ended, argued at two employment tribunals he should have been protected under whistleblowing regulations.

The tribunals ruled HEE was not subject to whistleblowing law because it was not strictly his employer.

But Friday's Court of Appeal judgment sends the case back to tribunal to decide whether HEE substantially determined the terms and conditions of Dr Day's working contract and can thus be judged an employer subject to whistleblowing law.

The Royal Courts of Justice has ordered Dr Chris Day's case be heard at another employment tribunal. Credit: PA

Dr Day's campaign website said the judgment also "clarifies the law for huge numbers of agency workers and workers in triangular working relationships that are subject to multiple organisations".

HEE has denied discriminating against Dr Day because of his whistleblowing.

A spokesperson for the British Medical Association said it had negotiated an agreement with HEE in 2016 which "offers contractual protection enforceable in the County Court or High Court".

"The BMA's primary concern has always been and remains to ensure the strongest possible protection for doctors in training who raise concerns at work," the BMA said.

"On the basis of today’s judgment, which is subject to appeal by HEE, the case has been remitted to the Employment Tribunal so that the issues can be re-considered on the basis of further evidence."