Please do not misrepresent what I say. All that I have said is that studying engineering may be of use to the OP as a lawyer.
Your claim to "know what you are talking about" is not persuasive. You appear to have no personal experience of commercial legal practice (a field in which I have worked since the 1980s). You queried above whether there would be many cases about cars. Legal work about cars is voluminous, as anyone familiar with commercial legal practice would know. I add that practising barristers do not work in firms, they group together in sets of chambers, which are not firms. Some barristers take jobs in law firms, but by doing so they in effect become solicitors, whether or not they retain their membership of the Bar.
In any event, the automotive sector is just one example amongst several of an industrial sector in which a background in general engineering might be of use to a practising lawyer.
Your position on this thread appears odd. You have gone from telling the OP that he should study law, to chiding the OP for proposing to take an engineering place, to suggesting that the OP would be better going to Brookes (a suggestion which is not helpful in the context of someone seeking a commercial legal practice, who will be competing for entry level positions against graduates of Oxford, Cambridge, and other high ranking universities).
On a general point, I invite you to reflect that this forum is for the assistance of people thinking about their education and careers. It is not about winning points, or proving that you are an expert on everything. No doubt you are an able maths teacher and helpful to those you teach. It is possible, however, that others may possess knowledge and experience which you do not possess.
OP, you can judge for yourself which (if any) of the comments on your thread are helpful.