  Legal Artificial Intelligence (LegalAI) focuses on applying the technology of
artificial intelligence, especially natural language processing, to benefit
tasks in the legal domain. In recent years, LegalAI has drawn increasing
attention rapidly from both AI researchers and legal professionals, as LegalAI
is beneficial to the legal system for liberating legal professionals from a
maze of paperwork. Legal professionals often think about how to solve tasks
from rule-based and symbol-based methods, while NLP researchers concentrate
more on data-driven and embedding methods. In this paper, we introduce the
history, the current state, and the future directions of research in LegalAI.
We illustrate the tasks from the perspectives of legal professionals and NLP
researchers and show several representative applications in LegalAI. We conduct
experiments and provide an in-depth analysis of the advantages and
disadvantages of existing works to explore possible future directions. You can
find the implementation of our work from https://github.com/thunlp/CLAIM.
