legal-citation-parser 0.3.0

Extracts metadata from Canadian legal citations

legal_citation_parser v 0.3.0

Extracts metadata from Canadian legal citations.

Although legal citations are typically short strings, they contain a great deal of information compressed into a relatively small package. This Python module is designed to extract and standardize that data from from legal citation strings. This module can currently handles the following citation types:

• Neutral citations (Canadian);
• Supreme Court Reader (SCR) citations;
• CanLII citations.

Version 0.3.0 brings significant reliability and performance improvements. Specifically, the database mapping different courts and tribunals to their unique codes has been completely redone, improving the function's overall performance and accuracy.

Metadata

Basic citation string

The module currently extracts the following from raw CanLII citation strings:

• UID. The decision's unique ID. Corresponds to the CanLII API's caseId variable.
• Atomic citation. The citation's human readable unique ID.
• Style of cause. The human readable case name.
• Citation type. The type of citation parsed.
• Year. The decision's year.
• Decision number. The decision's number.
• Jurisdiction. The province, territory, or federal jurisdiction the case was heard in.
• Court name. The human readable court level.
• Court level. The relative level of the court.
• CanLII URL. The decision's URL on canlii.org

CanLII API

The module is also able to use the CanLII API to retrieve additional metadata and other potentially useful case information, including:

• Short URL. The decision's short URL.
• Language. The decision's language or languages.
• Docket number. The decision's docket number or numbers.
• Decision date. The YYYY-MM-DD the court issued the decision.
• Keywords. A 'list' of keywords supplied by CanLII, separated by a '—'.
• Categories. A 'list' of categories supplied by CanLII, also separated by a '—'.
• Cases cited. A list of decisions (including databaseId, caseId, title, and citation) the case cites.
• Cases citing. A list of decisions (including databaseId, caseId, title, and citation) that cite the case.

Installation

pip

From the command line:

pip install legal_citation_parser

Usage

In Python 3.x:

>>> from legal_citation_parser import parse_citation

Kwargs

• verify_url: Pings a program-generated long_url . If unsuccessful, the function checks the same URL with the alternative language selected (i.e., "fr" instead of "en", and vice versa). Returns None if neither URL ping successfully.
• metadata: Retrieves CanLII metadata. Requires a CanLII API key.
• cited: Returns a list of cases a decision cites. Requiees a CanLII API key.
• citing: Returns a list of cases that cite the decision. Requires a CanLII API key.

Example calls

parse_citation("R v Sutherland, 2022 MBCA 23", verify_url=True, metadata=True)

Should produce:

{'uid': '2022mbca23',
 'style_of_cause': 'R v Sutherland',
 'atomic_citation': '2022 MBCA 23',
 'citation_type': 'neutral',
 'scr_citation': None,
 'year': '2022',
 'court': 'mbca',
 'decision_number': '23',
 'jurisdiction': 'mb',
 'court_name': 'Court of Appeal of Manitoba',
 'court_level': 'provincial appellate',
 'long_url': 'https://www.canlii.org/en/mb/mbca/doc/2022/2022mbca23/2022mbca23.html',
 'short_url': 'https://canlii.ca/t/jmnrg',
 'language': 'en',
 'docket_number': 'AR21-30-09591',
 'decision_date': '2022-02-24',
 'keywords': 'Criminal law — Murder — Second degree murder — Evidence — Admissibility',
 'categories': 'Criminal or statutory infractions — Evidence — Practice and procedure'}

Example call:

parse_citation("R v Sutherland, 2022 MBCA 23", call_api_cases_cited=True)

Should produce:

{'uid': '2022mbca23',
 'style_of_cause': 'R v Sutherland',
 'atomic_citation': '2022 MBCA 23',
 'citation_type': 'neutral',
 'scr_citation': None,
 'year': '2022',
 'court': 'mbca',
 'decision_number': '23',
 'jurisdiction': 'manitoba',
 'court_name': 'Court of Appeal of Manitoba',
 'court_level': 'provincial appellate',
 'cited_cases': {'citedCases': [{'databaseId': 'csc-scc',
    'caseId': {'en': '1956canlii541'},
    'title': 'Chibok v. The Queen',
    'citation': '1956 CanLII 541 (SCC)'},
   {'databaseId': 'nbca',
    'caseId': {'en': '2021nbca3'},
    'title': 'Currie v. R.',
    'citation': '2021 NBCA 3 (CanLII)'},
   {'databaseId': 'csc-scc',
    'caseId': {'en': '1982canlii33'},
    'title': 'Graat v. The Queen',
    'citation': '1982 CanLII 33 (SCC), [1982] 2 SCR 819'},
   {'databaseId': 'onca',
    'caseId': {'en': '2018onca494'},
    'title': 'R. v. Ajise',
    'citation': '2018 ONCA 494 (CanLII)'},
    ...
   } 

v 0.3.0 updates

• Court code & URL constructor overhaul
• URL construction on by default, relegated verification pings to edge cases

Contributing

Contributions to improve this module are welcome. You can contribute by:

• Reporting bugs
• Suggesting enhancements
• Sending pull requests with bug fixes or new features

License

This project is licensed under the GPL 3.0 License - see the LICENSE file for details.