Has anyboady heard of the QS Ranking and how reliable it is. I have read that they evaluate 3.500 universities in research and tecahing and 14,000 programs. It's realeased in the UK but is it trustworthy?

Hello Derecho_espana
Although the QS Ranking is one of the few worlwide rankings it is not very strong on law school rankings. They cover all sorts of different subject fields and act as an opt in service so not every University is considered and it is possibly biased.

Criterias they rank Universities on are
research quality amongst academic productivity
teaching
employability
internationalization
facilities
academice productivity
online distance learning
social responsibility
innovation
arts & culture and
inclusiveness

For UK law schools, the Guardian ranking is a good starting point:

http://www.theguardian.com/education/ng-interactive/2015/may/25/university-guide-2016-league-table-for-law