The Crown Prosecution Service has begun appeal proceedings with the High Court to overturn the acquittal of the Hatzola ambulance drivers it claims were illegally using blue lights and sirens to attend medical emergencies.
If the appeal is allowed, it could lead to a ban on community ambulance services across the UK using lights and sirens.
Greater Manchester Police and the CPS lost their attempt last month to prosecute two drivers for Hatzola, the Jewish emergency medical service, after they attended a crash scene in north Manchester.
Police argued that their vehicles were not real ambulances.