  This paper presents a new test collection for Legal IR, FALQU: Finding
Answers to Legal Questions, where questions and answers were obtained from Law
Stack Exchange (LawSE), a Q&A website for legal professionals, and others with
experience in law. Much in line with Stack overflow, Law Stack Exchange has a
variety of questions on different topics such as copyright, intellectual
property, and criminal laws, making it an interesting source for dataset
construction. Questions are also not limited to one country. Often, users of
different nationalities may ask questions about laws in different countries and
expertise. Therefore, questions in FALQU represent real-world users'
information needs thus helping to avoid lab-generated questions. Answers on the
other side are given by experts in the field. FALQU is the first test
collection, to the best of our knowledge, to use LawSE, considering more
diverse questions than the questions from the standard legal bar and judicial
exams. It contains 9880 questions and 34,145 answers to legal questions.
Alongside our new test collection, we provide different baseline systems that
include traditional information retrieval models such as TF-IDF and BM25, and
deep neural network search models. The results obtained from the BM25 model
achieved the highest effectiveness.
