If he is covered by an insurance policy , which includes third party cover or the cover is third party only , then a civil action by the taxi driver , would be dealt with by the insurer .
The assumption made in my previous answer was that he was driving under an insurance policy , with at least the minimum cover , as i have stated above .
Incidentally , if he was driving without third party cover , then the taxi drivers claim would most likely be directed to the ( MIB) Motor Insurers Beureau .
If they ,for some reason would not deal with the claim ; then the taxi driver could then pursue the civil,action directly against your brother ; but there would be little point in doing that if your brother did not have any resources to meet such a claim .