Just to put some balance into this whole situation, and reassure everyone that people do sometimes make an “honest” mistake (I’ve been late for paying my car tax before because I forgot to!) by missing their car tax renewal date.
That said, if it’s 2 months out (not 2 weeks), he’s driving around like a tit, and the car is in a very poor state of repair with bad tyres, then all probability points to the fact it is being driven around totally illegally, and with probably no MOT and insurance (possibly even the driver has no license!) and therefore he is a menace to anyone else on the road.
Remember, it’s all too easy to penalise the law abiding citizens amongst us that make a small mistake on occasion such as paying their car tax late, or doing 35mph in a 30 zone, as we get issued with an automatic fine etc. For those who just don’t care, and register cars at false addresses, or don’t register them at all, drive around with no MOT/Tax/insurance or even a license, you’ve actually got to physically catch them in the act in order to be able to do something about it. And seeing as road policing is going down the route of even less policemen on the road, and more and more cameras, they’re literally encouraging those who have no regards to the law to carry on doing so!
FWIW, in this case, unpaid tax on the car is not what I’d be reporting him for. I’d be reporting him for driving threateningly/dangerously and having illegal tyres on the vehicle. Let the coppers discover its got no tax either!