Ontology design is known to be a difficult task, requiring much more than expertise in an area or competence in logic; legal ontology design, due to the complexity of its domain, makes those difficulties worse. This may be partly due to poor support for requirement analysis in existing tools, but there is also an inherent gap between the purely logical constructs and methods that are expected to be used, and the actual competences and thought habits of legal domain experts. This paper presents some solutions, based on ontology design patterns, which are intended to make life of legal ontology designers easier. An overview of the typical tasks and services for legal knowledge is presented, the notion of ontology design pattern is introduced, and some excerpts of a reference ontology (CLO) and its related patterns are included, showing their utility in a simple legal modeling case.