These threads happen all the time, year after year. I say, reading in advance doesn't help. Then there's a tantrum by the school student.
But reading in advance doesn't help. You won't get books that'll help. The books you use at university are big £30-50 textbooks prescribed by the lecturer for the particular course you are doing, and they go out of date every year. Usually they're written by your lecturer, a) because even a professor won't know that many cases/material in other books, they'll know what they've written in the textbook and b) they make money. Criminal law is one module out of 12 which you do in your degree. You can't possibly do enough introductory reading to help you in any real way. In the exam, you might end up selecting your topics down to fraud, theft etc and miss out sexual offenses or something because there may be 3 questions you have to answer out of 10. You just don't know until you've worked really hard, you know the course you're on and you've studied the exam papers and structure closely.
The best thing you can do is read The Guardian legal and media sections, and perhaps even read the FT - which you won't understand, but you can try. Another thing is to read literature which will help your writing to improve. If people don't know what the study of law involves though, it does beg the question why people want to study it at university for three years. I skimmed through the Letters book once, it seemed ok.