Catrin's research encompasses three key themes. Firstly, Catrin researches Welsh dimension to the law. Accordingly, in 2005, she completed her doctoral thesis on the use of the Welsh language in the legal system and has since published work on the impact of language legislation on linguistic behaviour.
Secondly, Catrin undertakes research in to bilingualism in the law, and is therefore interested in the linguistic differences between legal texts produced monolingually and bilingually. Linked to this is Catrin's interest in the production of legal texts in dominant and minority languages.
Thirdly, as someone with an interest in theatre, both as a performer and a writer, Catrin is also interested in the engagement between theatre and the law, and has therefore published work on the law in Shakespeare, and is currently working on an article on the theatrical process as a method for exploring the impact of legislation.