This fascinating post by Dr Carol O’Sullivan at the University of Portsmouth may be of interest to translators and lawyers alike – sharing an interest in how words are used.
http://matsnews.blogspot.com/2011/11/google-n-grams-and-translation.html

It describes how collections of texts from 1500 to 2008, in several languages (Englishes, simplified Chinese, French, German, Hebrew, Spanish and Russian), can be used to examine synonyms, neologisms, and even to compare ‘competing words’.

I did a little test following Carol’s instructions, to compare “claimant” and “plaintiff”. Here are the results, for American English and for British English between 1800 and 2008. Note that the y-axis scales differ.

We can clearly see the jump in the use of “claimant” in the UK following the entering into force of the Civil Procedure Rules in April 1999.

American English

British English

Of course, as Carol says, these are crude readings, and to be more relevant to the law the corpus should be limited to legal documents only, but it is certain that they provide a very interesting glimpse for those interested in the development of language.

It is also a super-fast tool, and extremely easy to use. Tell me which words you compare!
http://books.google.com/ngrams/

You may also be interested in this related post here.