I understand that the question is intended to refer to motor tax, rather than Vehicle Registration Tax. I have no plans to introduce an exemption from motor tax in circumstances where the owners of tractors become incapacitated. An application for a refund of motor tax may be made where the owner of a vehicle has ceased to use that vehicle due to illness, injury or other physical disability, provided that there are at least three months remaining on the disc at the time of application. However, refunds are not made where the annual rate of duty applicable to a vehicle does not exceed €119. Refunds would, therefore, not be made in respect of agricultural tractors where the annual rate of tax is €102, but may be made in respect of general haulage tractors, where the annual rate of tax is €333.
It should also be noted that there is a facility to declare a vehicle off the road where it is not going to be in use for a period of time. Such a declaration can be made at any time during the last month of an extant motor tax disc.