hi

I do have a BA in political science but I would prefer to my masters some public law field, might be specialized on europe or international law. are there any universities which would accept students from other studies fields for their MA in law?

it can be done! check the admission requirements by every single university you are interested in, i am sure that some of them do not require you to have a BA of laws degree!!!

Most European universities will not require an LLB or JD, but you do need to check the individual requirements of all of them.

This article also addresses some options: http://www.llm-guide.com/article/213/llm-programs-for-non-law-graduates