Is it against the rules to see someone's exam answers after the exam?
Certainly it wasn't illegal in the technical sense and it is very unlikely, though not impossible, that some local rule would prohibit it. In fact, it ought to be entirely permissible for one student to aid the learning of another in this manner.
Even working together on &quot;possible&quot; exam questions before the exam should be permitted, even encouraged, IMO.
The point of it all is learning, not grading. There shouldn't be secret information.
On the other hand, there are some things that are best learned through struggle and not by reading answers. On a math test, for example, seeing the answer is very different from generating it. As a learner, you want to strive, as much as possible for insight, especially in those subjects that you are most interested in. That insight comes from hard work.