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week05.md

Week 5 Study Guide: Privacy

Big Picture

Privacy is not one simple, natural thing. Our current legal/technical approach (Fair Information Practices, PII, notice-and-consent) was built in the 1970s U.S. out of fear of big government databases. It treats privacy as individual control over personal information. In today's datafied world (data circulation, ML, tracking, inference), that approach falls short. Contextual integrity (CI) is a better tool: privacy = appropriate information flows that match the norms of a context. Pressly goes further: even CI still assumes information already exists. His argument is that privacy's real value is preventing information from being created in the first place and protecting oblivion.

Lecture 11: Privacy Foundations

Main claim

Privacy is not one simple, natural thing. The word bundles many ideas: freedom of thought/speech, control over your body, solitude at home, control over personal info, right to be forgotten, freedom from surveillance, protection of reputation, protection from searches. It is sociotechnical and contingent. It came from a particular history, not from nature.

Fair Information Practices (FIPs / FIPPs)

  1. Notice / Awareness: no secret record-keeping systems; you can find out what's in your record and how it's used.
  2. Choice / Consent: you can stop info collected for one purpose from being used for others without your consent.
  3. Access / Participation: you can correct your record.
  4. Integrity / Security: organizations must keep data reliable and prevent misuse.
  5. Enforcement / Redress: formal enforcement and ways to fix/compensate harm.

Personally Identifiable Information (PII)

  • NIST definition in U.S. security/privacy law: (1) info that can distinguish or trace identity (name, SSN, biometrics) plus (2) any info linked or linkable to an individual (medical, financial, etc.).

Technical contributions

  1. De-identification / re-identification: removing name, SSN, etc. is not foolproof.
    • Latanya Sweeney (2002): 87% of Americans uniquely identified by zip code + birth date + gender (linked medical data to voter list).
    • Netflix Prize dataset (2006-07) users can be re-identified easily, and second contest canceled after privacy lawsuit.
  2. Differential privacy (Cynthia Dwork et al., 2000s): privacy loss can be mathematized; add random noise to prevent re-identification while keeping analysis useful. Example: 2020 U.S. Census. Can be used for ML training data.

Limits of the inherited paradigm

This 1970s framework:

  • Focuses on individuals' personal info/PII, not collective impacts.
  • Relies on individual self-management decisions (usually at sign-up).
  • Assumes moment-by-moment decisions, not cumulative effects.
  • Assumes the issue is controlling movement of existing info, not preventing its creation.
  • Equates ethical with legal, which quietly narrows the discussion.

New problems it doesn't handle: data circulating far beyond original context, re-identification by merging datasets, new modes of collection, easy surveillance, algorithmic judgments/predictions, ML training sets, data capitalism.

Lecture 12: Privacy in the World

Terms of service

  • Clicking "sign up" = you enter a legal relationship; you get the service in exchange for information.
  • Problems: puts the work on the user; options are basically binary (opt in or don't participate), which steers you to opt in; companies can assume users don't read; it's all about "you" (individual).

Examples

Case 1: Havasupai blood samples

  • Havasupai tribe gave blood samples to Arizona State University researchers; samples were used for research beyond what they expected (returned in 2010).
  • Lessons: Identity/positionality is collective and relational, not just individual. Consent, but not just consent. Sovereignty (self-governance) is more than ownership, tied to colonial relations and histories.
  • Takeaway: expectations, relationships, and contexts matter.

Case 2: Crisis Text Line (2022)

  • Crisis Text Line (mental health crisis hotline, nonprofit) shared conversation data with Loris.ai, a for-profit AI spin-off (machine learning to make customer support "more human/empathetic"). CTL stopped after criticism.
  • Data was "anonymized," "scrubbed of PII," and users had "consented" → so FIPs/PII thinking says it's fine.
  • Shortcomings: manipulates expectations of caring human relationships; consent in moments of crisis is questionable; contextual shift (personal trauma → automated customer service); commercial product without compensating the people who provided the data; benefit ≠ who provides data; where's the responsible line between non-profit and for-profit?

Case 3: TSA semi-automated body scanners

  • TSA did a Privacy Impact Assessment with FIPs; disabled data storing, blurred faces, collected no other PII. Later moved to generic outline avatars (DHS 2022 measures for transgender/non-binary travelers).
  • Shortcomings: privacy here isn't about PII! It's about the body, dignity, values, norms; categorization (male/female bodies as the norm, "normal vs abnormal"); power dynamics: some people get extra screening, who is seen as suspicious/a threat.

Limits of "privacy as individual control" in the datafied world

  • Implications go beyond the individual who consents; strong incentives to get consent unobtrusively; is the individual (signing up in advance) even the right agent?
  • Harm happens even with non-identifiable info: metadata, inferences/correlations/ML.
  • Too many data sources to combine; user exhaustion; data reused far beyond context of collection.
  • What's at stake is more than privacy: discriminatory treatment, manipulation, decisional interference, dignity, sense of self. People already experience privacy/exposure differently based on power.

Reading: Malkin, "Contextual Integrity, Explained"

Core thesis

Privacy = appropriate data flows, judged by conformity with expectations, between people in relationships, in specific contexts.

  • A context has integrity that must be respected for people to feel privacy is secure.
  • Helps identify what causes privacy problems (e.g., context shifts) and suggests technical moves: collect least data possible; use it with respect.
  • Dictionary definitions of privacy are too vague. Laws (GDPR, CCPA) don't define privacy; they list rights and duties. Something can be legal yet feel like a violation.
  • We need a model that explains past privacy scandals and predicts future ones.

The four ideas

  1. Privacy = appropriate information flow.
    • Info flow = transfer of knowledge from one party to another (patient → nurse → doctor → computer → hacker...).
    • Rejects binary models (secret vs. not, private vs. public, sensitive vs. not). Example: you tell your doctor health info and your accountant finances, but it would feel wrong if your accountant asked for your medications. And public info (store visits) becomes invasive when aggregated into a profile.
  2. A flow is appropriate if it matches contextual norms.
    • Privacy is violated when flows breach legitimate contextual informational norms.
    • This is not procedural: following FIPPs/informed consent/encryption isn't enough. "Clicking 'I accept'" doesn't make problems vanish.
    • Norms = commonly held expectations. Can be explicit/implicit, legal/social, local/societal, changing. Examples: teacher shares grades with guardians only; therapist keeps confidences unless patient in danger; citizens report income but government doesn't publish it.
    • Norms must come from real people's expectations (find out by asking), not derived from first principles or one person's opinion.
  3. A norm has (at least) 5 parameters: data type (what info), data subject (who it's about), sender, recipient, and transmission principle (constraints on the flow: consent, warrant, notice, reciprocity, legal requirement, Chatham House Rule...)
    • If one parameter changes, the whole flow may become inappropriate.
    • Actors are roles, not identities (your doctor who is also your friend).
    • Purpose/use may deserve its own parameter. Example: smart speaker data used to answer queries = fine; used for advertising = company switches role to advertiser.
  4. New flows are evaluated through context using 3 layers: interests of affected parties, ethical/political values (justice, equity, free speech), and contextual functions, purposes, and values (e.g., does it undermine the purpose of health care?). A new flow can be good (e.g., disease outbreak notification to public health).

Four practical lessons

  1. Think beyond binaries. Example: voice assistants (Alexa) using human contractors to listen to recordings: data never left the company, but the new flow (humans listening, permanent record) broke expectations.
  2. Check expectations, not checklists. Fine print isn't a defense. Even PETs can fail: private browsing misunderstood; Do Not Track header itself became a fingerprinting signal.
  3. Account for the complete context. Social media "Like/Share" buttons are fine on news sites, but questionable on health sites. People are wary of humans (vs. machines) seeing data and of third-party sharing.
  4. Consider the consequences: link to contextual purposes. Example: remote proctoring / student surveillance: does it help or hurt learning?

Limits of CI

  • It's a model to predict feelings, not how people actually think; people act on emotions/intuition.
  • There may be other factors beyond five parameters.
  • It favors established norms (e.g., workplace salary secrecy norm may hurt workers/minorities).
  • Harmless data can be composed into invasive profiles (famous example: store predicting a woman's pregnancy from shopping history). CI's answer: higher-order/inferred data should be judged on its own terms; expectations "travel down" to the source data.

Reading: Pressly, The Right to Oblivion

Core thesis

Privacy is valuable not because it lets us control information, but because it protects against the creation of such information in the first place. Privacy protects and produces oblivion.

Key arguments

  1. We are "blinded by information." More information ≠ seeing more clearly. We lose sight of valuable areas of life that depend on limits to what is knowable. ("You are your data"; people called "data subjects"; conversation as "exchange of information.") Like being "impoverished by money": you view too much of life in dollars and cents.
  2. "Nothing in excess": the Delphic maxim next to "know yourself." Herzog: a house becomes uninhabitable if you illuminate every dark corner; same for a marriage.
  3. The Ideology of Information: the unspoken assumption that information naturally exists in human affairs and that any aspect of life can be turned into data. It:
    • Naturalizes the existence of personal information before asking what privacy is for.
    • Reduces privacy debates to "control, protect, or restrict access to info that already exists."
    • Serves surveillance states and capitalists (Marx: ruling ideas = ideas of the ruling class). It marks the "boundaries of resource extraction."
    • By the time you use "privacy settings," "it's already too late": the platform already has the data.
  4. Even privacy's defenders fall for it. The Stanford Encyclopedia's "informational privacy" definition, and views like contextual integrity, "control," "access," "flows," accept the information framing. Companies touting new "privacy features" is cheerleading for a diminished value of privacy.
  5. Neoliberal critique (Bernard Harcourt): privacy shifted from a humanistic value to something with costs and benefits, a type of property that can be bought and sold in a market. ("Privacy settings," privacy policies, services traded for data.) Pressly says the consent critique (coercion, power asymmetry) is true but doesn't address privacy as such.
  6. Privacy ≠ secrecy ≠ hiding ≠ anonymity ≠ confidentiality.
    • Secret: must be known definitively by someone; durable (shared secrets still secret; enables blackmail). Kid says "It's a secret" (fine) vs. "It's private" (odd). "Secret life" vs. "private life."
    • Privacy: not durable, is violated/destroyed when breached. A Peeping Tom can't "be in on" your privacy.
    • "Nothing to hide" slogan is fatuous, because hiding is for those with something to hide; privacy is for something else.
    • A lie can preserve a secret but not privacy, because it creates information (false) where there was none.
  7. Oblivion = a form of not-knowing where there is no fact of the matter, only ambiguity and potential; can't be said to be "x or not x." It's resistant to articulation. It's not a void; it can be encountered and respected in daily life.
    • Root: Latin oblivio (forgetting). Connects to being "oblivious" (not knowing and not suspecting there's anything to know), right to be forgotten, Acts of Oblivion (Treaty of Westphalia, 1648: "perpetual Oblivion" after war).
    • Respecting privacy = deliberate obliviousness: "It is as if it never happened," not just "I won't tell anyone."
    • Examples: neighbors arguing through the wall (overhearing ≠ violation, but keeping a journal or putting your ear to the wall shifts from obliviousness to suspicion); a pushy acquaintance treating you as a "repository of information" instead of a person with unknown depths; the hidden camera in a park (obliviousness vs. mystery vs. suspicion feel different).
  8. History matters: modern privacy began in the 19th century with the reaction to snapshot photography and mass media, opposing "humanistic moral rhetoric" to anti-human threats. Worries about "the end of privacy" are as old as the "information age" (mid-19th c.: photography, newspapers, Bertillon biometrics). Today's biggest novelty may be acceptance of the ideology of information, not any specific technology.
  9. Citizen's vs. artist's sense of privacy (Joshua Rothman): citizen = protect from others using info against us; artist (Woolf) = preserve life's mystery, leave things undescribed. Pressly argues these are not really separate; the civic idea of privacy has always been animated by the artist's sense.