So, if you're thinking about accepting your offer to the DPhil in Law at Oxford, I wanted to share my experience. Unfortunately, I have to say that I've been pretty disappointed with the program, and I think it's important for others to have all the facts before they accept their offers. This does not apply for MPhils and DPhils in Socio-Legal Studies which might be a completely different experience.
So, about the program itself - it's not very structured. As you know, you only have one mandatory course in legal methods during your first year. After that, you are on your own. You meet with your supervisor once a month if you're lucky, but it can be as infrequent as once every three months or even once a year. Professors are really busy with their teaching workload, and tend to prioritize BCL and BA students which makes it hard to get the support you need. Remember that Oxford has a tutorial system in which professors are expected to teach one to one tutorials on top of their lectures and sometimes even seminars. On top of that they have to worry about their own research so not a lot of time for PhD students. Of course, this can be different if you have a really wonderful supervisor who goes the extra mile for you but we aware of the structural demands of professors at Ox.
I want to highlight three main issues you should think about before applying. First, every year you have to pass three "tests" to continue with the program ( as you know, these are the QT, confirmation and the final viva). If you fail, you can be downgraded to a Master of Letters (M.Litt) or not allowed to continue the program at all. The problem is that there are no clear indications of what makes a "good" research proposal, which can be really stressful so keep this in mind. Think basically that after 1, 2 or 3 years you can be downgraded to an M.Litt and not being able to continue with your doctorate- and yes sadly this happens- after that you will not get any fees back of course for your "lost" years. I still think that the majority of the students pass these exams and are allowed to graduate, or I hope at least.
Second, the program is too expensive in my opinion, especially if you're an international student for what you get in return. Even with scholarships, living in Oxford is very expensive. The quality of supervision and courses for DPhil students is basically not existent- we don't even get an office and you are always hearing that the Law Faculty doesn't have money for DPhil students. There's also a myth that graduating from Oxford will allow you to work in top universities around the world as an academic, but I would take that with a grain of salt. Many go back to practicing law because the job prospects in legal academia are very limited right now. Some work at Oxford temporarily, but the pay for post-docs and professors is really low. (There was an article on The Economist about this that you could look at titled Oxford Diversity Crisis, I think)
Finally, there's no impartial mechanism for complaints about supervisors. This creates a lot of arbitrariness in an already unequal power relationship, and it's easy for supervisors to get away with neglect and bad supervision. I have heard horror stories, and basically there are not any accountability mechanism for supervisors doing a bad job. You should check with current DPhil students about potential supervisors but to be honest nobody is going to tell you that they have a terrible supervisor because at the end of the day we depend on our supervisors (for letters of recommendations, etc.) and it is not good practice to talk bad about our boss. My advise would be to try to be strategic and smart asking for information about potential supervisors. (I tried to post here some information about names that I have heard are good and bad for supervision but that infringes the community rules of TSR so sadly I am not allowed to share this information)
A few final tips - take a look at the current DPhil theses in Law and ask yourself if they're interesting to you, and do the same for the publications of the professors you want to work with. If you're an international student, be realistic about the costs and funding. Oxford's funding is scarce, so look for programs that offer full scholarships where you don't have to pay tuition in the UK, or even programs in continental Europe, like France, Germany, etc., that offer PhD programs in English.
I don't want to discourage anyone, but I hope this information is helpful to anyone considering accepting their offers. Finally, remember that your worth as a person or as an academic does not depend on being tied to prestigious universities or places. I say this because this is a struggle for many PhD students who put themselves in bad situations financially and emotionally just to have "an elite school" title attached to their names and in my view it is not worthy at the end of the day