330 likes | 558 Views
Mixing Legal and Non-legal Norms. Alexander Boer aboer@uva.nl. Overview. The ontological status of norms Why norms as preferences? Validity of norms as preferences Contrary-to-duty situations Normative conflict Further work Only in the paper Composition of non-legal preferences vs.
E N D
Mixing Legal and Non-legal Norms Alexander Boer aboer@uva.nl
Overview • The ontological status of norms • Why norms as preferences? • Validity of norms as preferences • Contrary-to-duty situations • Normative conflict • Further work • Only in the paper • Composition of non-legal preferences vs. • Composition of legal preferences (choice principles)
The ontological status of norms • ‘Norm’ is an epistemological category in assessment • Of a broken circuit board (norm group) • Of abnormal behaviour (normal) • Of undesirable behaviour (normative) • ‘Preference’ is an epistemological category in planning • Personal preference • Adopted preference (constraint) • In context of agent: norm = preference
Norms and Preferences in the Legal System • ‘Norms of analysis’ of involved stakeholders in drafting legislation • Legal norms adopted from legislation by addressees of legislation • Social norms adopted by addressees of legislation • Personal preferences of addressees • Adaptation of personal and social preferences to legal norms (evasion)
Uses of preferences • Making decisions constrained by legal norms (Legal Services Counter, E-POWER) • Assessing behaviour against legal norms (CLIME) • Assessing expected behaviour (adapted to legal norms) against ‘norms of analysis’ (E-POWER simulation) • Comparing two alternative sets of legal norms (E-POWER simulation) Almost always legal and non-legal preferences involved
Why? • My PhD Thesis • Newton workbench • Understandable Legal Knowledge Acquisition • Understandable representation method • Semantic Web (merging norms from different sources) • ESTRELLA Project • European project for Standardized Transparent Representations in order to Extend LegaLAccessibility • Legal Knowledge Interchange Format (LKIF) • Make everybody happy: represent whatever you want, apply reasoning rules depending on purpose
Ideas • Entity-Relationship-based (boxes and lines) method for representing normative statements in the Web Ontology Language (OWL) • Use mainstream Decision Theory concepts (choice, preference, composition of preferences) • Mixing with non-legal preferences • Use concepts from Knowledge Acquisition methodology • Concept Triads and decision trees/tables
Knowledge Acquisition as eliciting choices • Ontology and Decision Trees • Concepts and differentiae • Repertory grids • Triads: Binary choices, opposites • Choice reveals a preference • Norms • Binary choice between compliance and violation • Choice is guided by imposed preference (acceptance of a norm)
Norms as preferences? • Revealed vs. motivating preference • Preference for things vs. classes of things • Combinative vs. exclusionary preference • Conditional vs. absolute preferences? S subClassOf disjointWith A ¬A <
Representation in OWL • Entity-relation model (subject-predicate-object triples) • Very similar to description logics (KIF, LOOM, KRSS, etc.) but very different (graph-based) syntax • Separates statements about concepts (terminology) and instances (assertions) • No Unique Name Assumption for instances • Merging triples from different sources
Preference for classes of things in OWL • Operational semantics of preference relation is similar to =, =<, >=, >, < • Relation on concepts, not instances • Second order relation • Either not OWL DL but OWL Full, or two separate OWL DL terminological boxes • “Second order Reasoning” in practice simple • Not possible to represent that = and < are disjoint! • No disjointness on relations…
>= =< < = >
Validity of norms as preferences? • Contrary-to-duty situations • Chisholm, Forrester, Gentle Murderer, Reykjavic, etc. • Normative conflict • Conflict of disaffirmation • Disaffirming an imperative • Disaffirming a permission • Hill’s ‘intersection’ conflicts • Conflict of compliance • Other conflicts • Hohfeldian concepts, etc.
Conflicts of disaffirmation: disaffirmation of an imperative • Using the network facilitiesin the university building is prohibited. • Using WiFiin the classrooms is permitted.
Conflicts of disaffirmation: disaffirmation of a permission • Using the network facilitiesin the university building is permitted. • Using WiFiin the classrooms is prohibited.
Unresolved cases of disaffirmation • Symmetric subsumption of situation vs. alternatives: • Using the network facilitiesin the classrooms is prohibited. • Using WiFiin the university building is permitted. • No clear solution: • Is this simply not a conflict? • Does the most specific description of alternative take precedence? • Hill’s “intersection conflicts”?
Conflicts of compliance • ‘Impossibility of joint compliance’ (IJC) • In S you ought to both P and not P • Did you voluntarily enter into situation S? • Can you move out of situation S? • Example: • Police: night clubs ought to lock unguarded emergency exits • Fire department: night clubs ought not to lock emergency exits
Conflict between permissions? Elhag et al: “There seem to be other types of conflict as that between the permission for A to live in a certain house and a permission for B to destroy that same house. These conflicts need our attention and have to be embodied in a theory on normative conflicts.” • Neither agent has to deal with a circular ordering of alternatives • Both agents are free to act
Other cases of conflict? • Conflict of legal and non-legal norms • permission for A to live in a certain house and a permission for B to destroy that same house • permission for A to live in a house that is to be destroyed (given B’s preferences?) • A norm of analysis is violated… • Alternative: assumption of implicit right-duty relation between A and B? • Conflict of a norm with reality • Unrealizability of compliance with norm
Other work • Composition of preferences in Law vs. Decision Theory • Choice rules (Lex Specialis etc.) work because of restricted format for legal preferences • Additive (MAUT) and multiplicative (utility) composition in Decision Theory • Hohfeldian legal concepts • Right, duty, power, liability, etc.
Further work • ESTRELLA’s LKIF and Newton • Axioms on/off • Automated Problem Solving vs. evaluation queries • Isomorphism MetaLex legislative XML structures to OWL representation • Classification of sentence patterns • Normative statements about (application of) legislation • Choice rules defined in legislation • E.g. overruling Lex Posterior