To borrow from Donald Rumsfeld, there are known knowns and there are things we know we know, but we also know there are unknown knowns. No sooner had the Commons transport committee waded into this minefield earlier this week than my inbox was flooded with responses.

With certainty, we can say that MPs are not willing to see the current number of whiplash claims remain - and they blame personal injury claims for the rise in car insurance premiums. The transport committee wants the burden of proof lifted and placed on the claimant. Its report talks of ‘objective evidence’ of injury, or the injury having a ‘significant’ effect on the claimant’s life.

This makes two worrying assumptions. One is that current medical help is presumed not to be objective. The other is that insurance firms are not currently willing to take on cases they should have every chance of winning. The response from the affected sectors was predictably contradictory.

The Forum of Insurance Lawyers welcomed the report and noted that ‘legal costs attached to [whiplash] claims have been a defining factor in the inflation of claims costs’. The Association of British Insurers, with barely concealed glee, called for the ‘whiplash epidemic’ to be dealt with once and for all, and for lawyers’ fees to now come under further scrutiny.

In the blue corner, the claimant lobby fought to have its voice heard amid some partisan reporting in the national media.

The Association of Personal Injury Lawyers argued that injuries like whiplash ‘can be extremely painful and can often linger’, whilst the Access to Justice Group said there were ‘grave concerns’ over the parliament’s intervention. Such polar opposite reaction is nothing new, but does emphasise how fraught this issue has become.

Whiplash has become a convenient whipping boy for the British public’s confused anger at the cost of motor insurance. The driver on the street sees (or at least, believes) that motor insurance has sky-rocketed. Someone or something must be to blame.

Without doubt, the government must go after any solicitor or medical practitioner who knowingly flouts the rules and pushes through fraudulent claims. They’ll have a job proving it, mind you.

And therein lies the biggest problem with whiplash: proof. How are claimants to gain further proof of their injury beyond their doctor’s report? And can we truly tell apart the fake from the casualty?

Proof is the greatest known unknown. And it’s what makes this debate so difficult to win - and the solution (if indeed there is a problem) near-impossible to pin down.

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