I also looked at that reference, but as it doesn't define 'safely parked' and most of the other sites I looked at specifically mention switching off the engine that's what I'd go with. It makes sense - PC Plod can't tell without physically checking it whether a handbrake is on or off, whilst he can tell from outside the car whether the engine is running or not.

It's not in itself sufficient, of course, as otherwise one would be able to make calls from a 'stop-start' equipped car whilst stopped at the lights, so there's still a requirement to be stopped in an appropriate and safe place.

As for drinking at the wheel, now the American craze for take-away and drive-through coffee shops has crossed the Atlantic most people seem to do that! That'll probably be the next thing specifically made illegal...

I recall two cases at magistrate level. Firstly a lady got off as she hasn't turned her engine off while parked up. Reason was she had a new born baby in the car and had the heaters on. Second was jimmy Carr who claimed he was using his phone as a dictaphone so therefor not using the phone to make a call! His lawyer got him off that one. Black MY2013 SD4 GS Auto, Wood Company Armrest, Freel2 sticker.
Gone MY2010 Freelander 2 Manual TD4.e S, Alaska White.