Legal Calendaring as Logic Constraint Programming - jurisgpt/GrizlyUDVacator GitHub Wiki

Legal Calendaring as Logic Programming: A Framework for Temporal Reasoning and Rule Automation

This page introduces a formal, logic-based framework for modeling legal calendaring rules using concepts from computational linguistics, logic programming, and Answer Set Programming (ASP). It is designed for developers, legal engineers, and public interest technologists working on automating deadlines and procedural rules in litigation, especially in California unlawful detainer (UD) cases and similar high-stakes summary proceedings.

🧠 Why This Matters

Legal calendaring mistakes are among the leading causes of malpractice. Statutes and procedural rules use complex, nested logic involving:

  • Trigger dates,
  • Day-counting rules (court vs. calendar days),
  • Service method offsets,
  • Jurisdiction-specific rolling rules.

This logic can be systematically extracted, represented, and executed using formal logic systems. This framework helps encode calendaring rules as machine-readable logic and automates accurate deadline computation.

🧩 Core Framework Components

1. Temporal Constraints

Time Units:

  • calendar_days
  • court_days (excludes weekends and court holidays)

Trigger Day Rules:

  • Exclude the day the event occurs (exclude_trigger(start))
  • Include last day unless it's a weekend/holiday, in which case roll forward

Rolling Behavior:

  • roll_forward, roll_backward, or no_roll
  • May depend on federal vs. state logic (e.g., FRCP 6 vs. CCP § 1013)

Service Offset Rules:

  • Offset can be applied:
    • Before calculation (pre)
    • Directly included (mid)
    • After rolling (post)
  • Varies by service method: personal, mail, fax, electronic

2. Predicate Dependencies

Legal calendaring logic can be decomposed into interdependent predicates:

Predicate Description
served(X, Date) Date of service for filing X
method_of_service(X, Method) How the service was performed
trigger_date(X, Date) Computed date that starts time clock
due_date(X, Date) Final filing deadline
rolling_applied(Date, RolledDate) Final adjustment if deadline lands on weekend/holiday

3. Variable Types

Variable Type Examples
Temporal Date, Days, OffsetDate, DueDate
Entity X (filing), Method (e.g., mail)
Boolean/Flags landing_on(holiday), is_motion

⚖️ Rule Modeling in ASP (Answer Set Programming)

Here's an example encoding:

% Define base predicates
unit(calendar_days; court_days).
method_of_service(answer, mail).
served(answer, "2025-05-01").

% Offset rule for CA mail service
service_offset(mail, calendar_days, 5, pre).

% Rule to compute trigger date
trigger_date(X, TDate) :-
    served(X, SDate),
    method_of_service(X, M),
    service_offset(M, calendar_days, D, pre),
    add_days(SDate, D, TDate).

% Rule to compute final due date
due_date(X, FinalDate) :-
    trigger_date(X, TDate),
    count_days(court_days, TDate, 10, TempDate),
    roll_if_needed(TempDate, FinalDate).

This logic can be interpreted by ASP solvers like clingo to produce deadline timelines under formal guarantees.

🔄 Predicate Interactions

Interactions define how predicates influence each other:

  • Rolling interacts with due_date when the final day is not a business day
  • Offsets interact with trigger_date depending on jurisdictional rules
  • Multiple service methods and triggers (e.g., hearing date vs. motion date) can cause ambiguity unless explicitly resolved

🔎 Conflict Resolution Strategies

Problem:

Rules often do not specify whether “days” means court_days or calendar_days.

Solution:

Use interpretation hierarchy:

interpret_days(X, court_days) :- day_count_less_than(X, 10), not explicitly_specified(X).
interpret_days(X, calendar_days) :- explicitly_specified(X, calendar_days).

🏗️ Legal Reasoning Chain

The calendaring engine mimics a lawyer’s reasoning process:

  1. Find Authority: Locate the applicable statute or rule (e.g., CCP § 1013)
  2. Identify Time Unit: Court vs. calendar days
  3. Apply Trigger Rule: Exclude start, include or roll last
  4. Apply Service Offset: Mail, fax, electronic
  5. Perform Rolling: Weekend or holiday rules
  6. Output Due Date: Final computable deadline

📥 Metadata for Intake Systems

To automate this with precision, your intake system must collect:

Question Type
Date served? date
Service method? enum
Court jurisdiction? enum (State/Federal)
What type of document is due? enum (motion, answer, etc.)
Is a specific statute or rule cited? string or ref

🧰 Sample DSL for Rule Definition

RULE ComputeDueDate:
  INPUT: ServedDate, MethodOfService, Days, Jurisdiction
  STEPS:
    IF MethodOfService == "mail" AND Jurisdiction == "CA" THEN
        OFFSET = 5 calendar_days PRE
    ENDIF
    START = ServedDate + OFFSET
    COUNT 10 court_days FROM START
    IF LastDay IS weekend OR holiday THEN
        ROLL FORWARD
    ENDIF
  OUTPUT: DueDate

This DSL can be transpiled into ASP, Z3, or Python logic.

🧠 Use Case: California Unlawful Detainer Answer

Scenario:

  • **Event: Tenant is personally served with eviction (Unlawful Detainer) papers.
  • Service Date: Thursday May 1, 2025 (personal)
  • Deadline for tenant to file response to the lawsuit: 10 court days from the date he received in hand
  • Rule/Law: CCP § 1167 as amended by Assembly Bill 2347 (AB 2347), effective 01 January 2025.
  • Requirement:Tenant must file response within 10 days from date of service.

🧮 Computation

  • Exclude May 1 - the day papers received in hand is Day 0
  • Count 10 court days (skip weekends & holidays)
  • Roll forward if final day is on weekend/holiday
  • Definition of Court Days: Exclude Saturdays, Sundays, and judicial holidays.

Day 0 : Exclude the day of service.Thursday May 1 is considered Day 0. Day 1: Begin counting from: Friday, May 2 as Day 1. Saturday May 03-Skip holiday, Sunday May 04-Skip Day 2: Monday, May 5, Day 3: Tuesday, May 6, Day 4: Wednesday, May 7, Day 5: Thursday, May 8, Day 6: Friday, May 9, Day 7: Monday, May 12 Day 8: Tuesday, May 13, Day 9: Wednesday, May 14 Day 10: Thursday, May 15 = 📌 Deadline- File ON or BEFORE May 15.

📚 References

  • CCP § 1013 (California rolling/service rules)
  • FRCP Rule 6 (Federal computation of time)
  • CCP § 1167 (Time to respond in unlawful detainer)
  • California Rules of Court
  • Local Court Holiday Calendars

📌 Conclusion

This logic programming framework enables rigorous, testable, and automatable calendaring systems grounded in statute and case law. Whether you're building a tenant defense automation tool, a calendaring engine for attorneys, or a rules-as-code prototype, this approach provides the foundation for trustworthy legal automation.

🚀 Next Steps

  • Integrate this with a Python or Z3-based calendar calculator
  • Expand predicate library to handle multiple trigger types
  • Add support for local court holidays (county-specific)
  • Generate intake interview templates based on predicates
  • Generate proofs