I have no personal opinion either way, but for information purposes here's what Deerstalker said elsewhere..
The of taking road killed game, provided you did not kill it yourself, is unfortunately an urban myth. No game may be killed on taken in the UK without a valid game licence. All game is the property (live or dead) of the landowner who's land it happens to be on. The 1994 Deer Act states quite clearly that it is a criminal offence to enter any land (not your own) for the purpose of killing or the taking of deer (dead or alive). Often the game rights of adjoining landowers cover the whole of the road. In the case of there being different landowers each side of the road, then each landowners rights extend to the centre of the road. In this stituation, to pick up road kill from the road or verge would mean you are guilty of poaching.
Other roads are the property of local authorities and othe executive transport agencies. These roads, although, technically, in public ownership, do not give you any extra rights to pick up game. Such game is still not your property and you can be prosecuted under the game act, the 1994 deer act, the 1961 (or is '62) theft act (stealing by finding), as well as a possible conviction for poaching.
It is interesting to note that on summary conviction, the vehicle used to pick up such game will be confiscated by the the authorities.
As a professional deer manager, a member of The Humane Slaughter Association and a marksman on a retainer to defra, I would beg you all not to attempt to hit a deer in your car. At best your car will end up a write off, at worst you will end up dead (I think about 30 people lost their lives last year as a result of deer impacts).
The health issues are far reaching. As somebody said, you really don't know why these deer are hit by cars. or indeed how they died. I have been called out to dispatch road casualties which, have been hit because they are old, diseased, darted with anaesthetics or even contraceptives.
If I or a vet dispatch an animal, we don't take it home. It becomes the resonsibility of the landowner or council to arrange collection of the carcass by the knackerman for incineration.
As a professional stalker, not only are we trained (it's a hard course) in disease recongnition (how many of you would know where a deer's lymph nodes were and how to recognise such things as bovine TB?), but we also hold a large game meat hygiene certificate, so when you buy venison, not only can you guarantee it is clean fresh meat, but you can trace it to the stalker who shot it.
We stalkers know exactly where to shoot deer and with the correct weapons. This ensures a humane kill without damaging the gut. If the gut is ruptured, then the meat is contaminated and not suitable for human consumption. It is essential that the animal is bled and gralloched straight after death (no you don't hang it up from anything). The object of the game is to cool the carcass as quickly as possible (we have special tools to hold the chest cavity open to assist rapid cooling).
Gralloching a deer is nothing like paunching a rabbit.
Considering a deer involved in a RTA will suffer fatal trauma, you have no contol over disease, gut damage, drugs, haemorrhaging etc.
Any deer that has cooled to, or near ambient temperature without being bled or gralloched is a health hazard and not suitable for human consumption
Food for thought maybe. (Pardon the appauling pun!)
Marts
good thing no-one reported it 
iv got plans to use all the beast but if theres anything left over ill offer it on this site
