Basic interview

Question 0

Ask open ended questions

Answer 0

List evidence and missing information
List who what when where questions and the possible replies in advance
Mirror - laugh together, mirror pace of speech, avoid arguments
Propose multiple stories and see what elicits a reaction
Look for guilt - guarded answers, vague, reluctant to offer additional info, dismissive, weak, illogical, linear (strict chronology)

Question 1

Baseline behaviour

Answer 1

Laughter
Body movement
Posture
Vocal quality
Reaction times and expressions

Question 2

Study the clusters

Answer 2

Non verbal clusters:
Grooming gestures,
Hand wringing,
Inward curled feet,
Stuff upper body, inappropriate stillness,
Slumped or self-protective posture,
Moving objects on table or floor,
Excessive sweating, breathing, finger-tapping,
Shift in blink rate,
Shrugs, clenched fists, palms turned up out of sync with dialogue,
Fake smiles
Closed eyes:

Verbal clusters:

Qualifying statements "as far as I know, to tell you the truth"
Repeating the question verbatim
Non-spontaneous response time
Weak and apologetic tone of voice
Dodging the question
Inappropriate detail
Short, clipped answers
Objections to irrelevant specifics
Whining about the interview itself

Question 3

Intuit the gaps

Answer 3

Statement gaps - between what someone says they were doing and the facts they tell you (went on the train but don’t have receipt for ticket);
Logical gaps;
Behavioural gaps (worked till 2.am although usually says he need 8 hrs sleep);
Emotion gaps

Question 4

Confirm

Answer 4

Ask the same fact-seeking questions but always in different ways;
Directly ask “how do you feel?”
Ask “what should happen to the guilty party?” (Guilty people tend to minimise punishment);
Ask “who do you think did it?” (Innocents tend to offer suggestions, guilty generalise);
Ask then to recall the details backwards;
Ask what you think would motivate someone to act as they did (innocents tend to co-operate),
Make clear you have facts the subject hasn’t given you;
Ask “what do you think will be the result of this investigation?” (Innocents tend to be more positive, deceitfuls go for “I hope it clears me/it should clear me”;
Ask questions that minimise the significance of the incident - you may get additional info;
Ask questions with multiple outcomes both of which suggest deception.

Accept you may be wrong and avoid asking “why” since it makes people defensive regardless I guilt.