Such is to say, rescind legislation (1983, I believe) that makes the wearing of seat-belts mandatory (in most cases): certainly in respect of adults; possibly in respect of children.
I'm aware of only two arguments, respectively central and supporting, advanced in support of this infringement of personal freedom: (i) that it saves lives/injuries; (ii) that it saves the state (i.e. the tax-payer) money, by reducing the burden on the NHS of treating road-related accidents. Each briefly in turn:
(i) Saving Lives/Injuries
This is probably true (overall) – I grant its intuitive plausibility. Though it is possibly false, to wit: disputes about whether the stats ('before' versus 'after') actually support the claim; 'risk compensation' effects (i.e. greater safety encouraging greater recklessness); classes of injury made actually more likely by the wearing of constraints. But either way, it's IRRELEVANT! An adult person's life is surely his to dispose according to his own lights, for better or worse, advisedly or not. Admittedly, other people, and even the state, may well possess a certain interest in the care that a person takes of himself, but can hardly be construed as posessing a right to his avoidance of carelessness. Any possible harm, as the philosopher J.S.Mill would have insisted (On Liberty), is simply too remote from them for their desires to trump his.
(ii) Saving Money
The argument here seems to be that (presumptive) private recklessness results in unreasonable (because reasonably avoidable) public costs; which, therefore, means that such behaviour is after all not a (clear) case of that purely 'self-regarding' activity in which J.S.Mill (as above) would have deemed state-interference to be illegitimate. Whilst not suggesting that Mill says the very last word on these matters he does at least say a first word, which advantages us with a working 'rule-of-thumb' where desires for liberty and security may pull in opposite directions. It is unfortunate, therefore, that the Saving Money argument renders the scope of his 'harm principle' practically pointless (and useless). By implication of that argument the principle is only deemed applicable in such cases as a person lives life by perhaps the precept of an Aristotelian 'Golden Mean' (i.e. moderation in all things), or some cognate continence. But by this standard of rightness there would be any number of common activities which, because involving some element of risk or even danger (bespeaking potential public costs in NHS-treatments, or whatever), which would thereby be opened to state interference.
Perversely, then, under this tortured interpretation Mill's harm principle, far from defending individual liberty has been transmogrified into an instrument of attack upon it. Which, so far as I can see, is what presiding seat-belt legislation represents.
Why is this idea important?
WHY MY IDEA IS IMPORTANT
Because every single day millions of presumptively adult human beings are subjected to restrictions the arguments for which implicitly deny their autonomy and responsibility; indeed, their notional adulthood itself.
Which truly vast abrogation of majors' civil liberties raises the matter of minors'. By legal definition, children are not (fully) autonomous and responsible: so, should their rides be state-regulated? Well, certainly there's more of a case to be made here. However, just because an individual isn't yet equipped 'to take his life into his own hands' doesn't automatically mean that the state should be doing it for him. My own instinct in the matter is that those adults who are parents, or others in loco parentis, ought be vested with primary care for their own kids; after all, if deemed incapable of responsibility even for their own children then the appelation 'adult' is surely misapplied in the first place. At the same time it is surely proper that the state should take some, albeit secondary, responsibility for those of its citizens who are not yet able to look out for themselves; just in case those who ideally should be looking out for them – i.e. parents/guardians – fall short of the ideal. So I'd suggest a framework of law that permits parents (or those in their stead) a fairly wide, but by no means unbounded, discretion in the matter.