[30] It should be noted that there may be a hierarchy between Charter rights and non-Charter and non-Charter rights. The Charter takes precedence over all laws of Canada. In addition, quasi-constitutional rights contained in human rights legislation generally take precedence over non-constitutional statutory rights (see, for example, subsection 47(2) of the Ontario Human Rights Code, R.S.O. 1990, CHAPTER H. 19). We first present a motivation for our work in the context of legal research in § 2. In Section 3, we then turn to related work. Then there are two studies, the first on manual annotation in section 4 and the second on automated annotation in section 5. The paper concludes with some conclusions in Section 6. A related and important distinction that should be made with respect to legal reasoning is the idea that the legal principles cited can be classified as ratio or obiter. As defined by Raz (2002): « ratio decidendi can be understood as such legal statements based on the established facts and on which the decision is based ». The statements that are usually included in the category of obiters are dissenting statements and statements that are « based on non-existent or intangible facts of the case » (Raz, 2002).
From a legal point of view, the main difference between ratio and obiter is that the former is binding, while the latter has only persuasive power. Branting (1994a) attempted to automatically identify and extract the ratio. Plug (2000) attempted to identify obiter statements. However, the distinction between ratio and obiter is not used in this work. Wyner et al. (2010) conducted a study to identify parts of reasoning using contextless grammars. Like Jackson et al. (2003), the study notes the following difficulties in identifying argumentation structures in legal texts: « (a) recognition of intermediate conclusions, particularly those without rhetorical markers, since more than 20% of conclusions are classified as premises for a higher-level conclusion; (b) ambiguity between argumentation structures. The results reported are: local – 59% accuracy, 70% memory; Conclusions – 61% accuracy, 75% recall; Non-argumentative information – 89% accuracy, 80% memory.
The methodology for applying statistical tools to annotated corpora was developed by Moens et al. (2007) to automatically recognize sentences that are part of the legal argument. The study achieved an accuracy of 68% for legal texts. Ashley and Walker (2013) aimed to « automatically extract argumentation-relevant information from a corpus of legal decision documents » and « construct new arguments from that information. » The preamble to the Ontario Human Rights Code, which is based on the Universal Declaration of Human Rights, also reflects societal values related to human rights and equality. To this end, four fundamental principles emerge from the preamble: Legal principles may be relativized, for example with conditions that may restrict the application of rules. It is also possible that the legal principles are « active » in the argument, but that they are derived from the text, in which case they cannot be commented on or used for a subsequent revision of the text. Legal citators, which represent tertiary sources, are systematized collections of legal reports that allow for faster search of cases and provide brief summaries of the handling of cases showing which cases were cited during the discussion. The first legal citations were printed on paper and their history goes back centuries to modern times; see, for example, the reviews of the history of Anglo-American legal citation (Cooper 1982) and American legal citations (Ogden, 1993a; Gerken, 2016). Paper citators are still in circulation, but there are some drawbacks to their manufacture and use. First, creating case summaries requires people to interpret the law, which can be time-consuming and expensive, and is often done by companies that offer citators as a service.
The practice introduces and maintains a certain degree of opacity on the law, as well as a dependence of lawyers on these citters. Second, paper tanks need constant updating because the common law can be changed whenever a new decision is made. Third, manual searching of the ever-increasing database of cases can be slow and not always efficient. Currently, LexisNexis and WestLaw, leading information service providers, offer electronic case citters. These tools allow regular updates of report databases and provide a Boolean toolbox that allows for more efficient searches. However, it is believed that e-citters still rely on humans to interpret case law in case summaries. It should also be noted that the results returned by citters often require the reader to interpret and extract the applicable law encoded in the reports. Zhang P, Silver H, Wasson M, Steiner D, Sharma S (2014) Knowledge network based on legal issues.