Best Practices for Building Legal Knowledge BasesMichael Poulshock

Wolfram Data SummitSeptember 4-5, 2014

<lighthearted_introductory_banter/>

About me

oLegal knowledge engineeroLawyer + programmeroWork at Exeter GroupoBuild systems that

automate law and policy

Automating the law?

oEncoding legal rulesoApplying the rules to fact

patternsoGetting legal conclusions or

“determinations”oEmbedding this functionality

in a larger system

Vocab

o Expert systemso Business rule engineso Knowledge baseo Knowledge engineeringo Policy automation / modelingo Decision support systemso Calculatorso Computational law

Examples

irs.gov/ita

Benefits of automation

oConsistencyoSpeedoCost-effectivenessoAuditabilityoBreadth of knowledgeoUpdated as the law changes

Best Practices

“An expert is a person who has made all the mistakes that can be made in a very narrow field.”

Niels Bohr

1. Declarative paradigm

oProcedural (step-by-step)oDeclarative (if-then)oPolicy rules tend to be

expressed declarativelyoProcedural representations

(such as flowcharts) do not scale well

1. Declarative paradigm

procedural declarative

the transaction is in compliance ifthe amount < $10,000 orthe date > 2014-12-31 orthe type = “Intracompany”

compliesQ[t_] :=amount[t] < 10000 ||date[t] > {2014, 12, 31} ||type[t] == “Intracompany”

2. Isomorphism

oCode should be structured similarly to the policy rules

oCorrespondence / traceability

oRule verificationoMaintenance

2. Isomorphism

the waiver of inadmissability is valid under 8 CFR 1207.3(b) if

the basis = “Humanitarian grounds” orthe basis = “Family unity” orthe basis = “Public interest”

2. Isomorphism - techniquesoUse domain vocabularyoFollow document structureo Include citationsoAdd code comments

documenting assumptions, etc.

3. Cross-trained developersoProgrammers lawyersoLawyers programmersoCenter of Excellence approachoHandling changes in the lawoFundamentally, this is

programming

Tree-like structure of legal rulesthe person is liable for the tax if

the person’s income >= $12,000 and

the person is not a tax dependent

the person’s income = ...

the person is a tax dependent if...

Tree-like structure of legal rules

Tree-like structure of legal rules

Tree-like structure of legal rules

4. Tool that can analyze the treeo Fundamental challenge:

oHow do you know what the inputs are for a particular goal?

oHow do you know which are relevant?

o Need a tool that can collect data in automated wayoDebuggingoDynamic interviews

5. Separation of policy rules

oFundamental tension between declarative rules and interview behavior

oDon’t want to hard code interview sequences

oBut we want a humane and empathetic user experience

5. Separation of policy rules

o Best practice is to separate policy logic from other types of rules, such as:o Interview sequenceo Interview messages and visibilityoData transformationoData validation

6. Time

Why time is complicated:

1. Laws change

2. Facts change

3. The way facts change matters

4. Points of reference change

6. Time

oHandling time can easily make a mess of your code

oNeed to address time early onoBackdrop of absolute timeoNeed functions and data

structures for handling time

7. Knowledge of ignorance

oNot all law is worth automating

oGranularityoModels are always

approximateo Systems need to know

what they don’t know and route those cases to humans

8. Sufficiently expressive languageoMany tools out thereoSome geared to business usersoMany not expressive enoughoMany not extendable

o Functional programming is preferable

o Conservation of complexity

9. General software best practices

a) Functional programming

b) Unit testing

c) Refactoring

Closing thoughts

o Law is inherently complexo Legal logic is fractal-esqueo Law is more computational than

it may first appearoWrapper / interface around the

law’s complexityoMaking the law more accessible

Michael Poulshockmpoulshock@gmail.comwww.linkedin.com/in/mpoulshock

Thank you!