courses

Structure of the Legal System

CS593: Digital Forensics — D. Kevin McGrath

Overview

Digital forensics experts must be able to testify in civil lawsuits and criminal trials. That means working with legal actors — judges, prosecutors, defense attorneys, and others. This lecture focuses on who those people are, how disputes escalate into courtroom proceedings, and how the workgroup of actors that staffs a courtroom operates. Importantly, DF investigations are not only about catching bad guys: forensics expertise is equally valuable for defending people who have been wrongly accused.


Disputes are the raw materials of a legal system. Legal institutions exist to help people resolve disputes they cannot resolve on their own.

How Disputes Develop

Researchers have identified three stages through which a dispute escalates (Felstiner et al., 1980–1981):

  1. Naming stage: A person recognizes that she has been injured. This can be immediate (identity theft) or delayed (asbestos exposure).
  2. Blaming stage: The injured party attributes responsibility for the injury to someone else. Self-blame interrupts the disputing process; disputes require blaming another.
  3. Claiming stage: The injured party demands redress — compensation, prosecution, an apology, or something else.

A dispute arises when the demand for redress is denied. At any point, a party may walk away (“lumping it”).

The Disputing Pyramid

The U.S. is not actually the hyper-litigious society it is sometimes portrayed to be. The disputing pyramid illustrates the attrition of disputes at each stage, from the broad base of social relations through grievances, claims, disputes, hiring lawyers, court filings, and finally — rarely — verdicts.

Most disputes are resolved before any stage of formal legal proceedings. Litigation is taxing, expensive, and heavily weighted toward parties with more resources. The number of lawsuits filed is tiny compared to the number of grievances in daily life.

The U.S. legal system is adversarial: the injured party and the party accused of causing the injury each present their version of facts to a neutral third party (judge or jury), who decides the outcome. Both sides choose what evidence to present and which experts to hire.

This contrasts with inquisitorial systems (common in Europe and much of Asia), where the judge controls what evidence is heard and directs parties to produce what the judge considers most important. In the U.S., the power to shape what the jury hears rests with the lawyers — not the court.

As a DF expert working in the U.S., you will always be working for one side or the other, not for some neutral arbiter.

Consequences of the Adversarial System

Criminal vs. Civil Justice Systems

  U.S. Civil Justice System U.S. Criminal Justice System
Parties Plaintiffs and Defendants (private parties) Prosecutors and Defendants (the State)
Goal Compensation Punishment
Standard of proof Preponderance of the evidence (~51%) Beyond a reasonable doubt (~85%)

Key points:


Courtroom Workgroups

Courts are adversarial, but they are also organizations. The concept of the courtroom workgroup captures the fact that judges, prosecutors, defense attorneys, and supporting staff work together repeatedly in recognizable patterns.

Key features of workgroups:

Courtroom Workgroup Goals

Eisenstein and Jacob (1977) identify four goals organized along two axes:

  External Goals Internal Goals
Expressive function Doing Justice Maintaining Group Cohesion
Instrumental function Disposing of Case Load Reducing Uncertainty

Members of the Courtroom Workgroup


Lawyers serve three main functions:

Resources matter enormously: large law firms can hire the best experts, sustain lengthy litigation, and shape legal standards in future cases through precedent. Ordinary people with ordinary lawyers are at a significant disadvantage.

Prosecutors

Defense Attorneys

  1. Fee-for-service: the best cost $500–$1,000/hour; quality varies widely.
  2. Public defenders: overworked, underpaid, but benefit from established relationships with prosecutors and often get decent plea deals.
  3. Court-appointed lawyers: often incompetent; disproportionately implicated in wrongful convictions.

Plea Bargains

Most criminal cases never reach a jury because the courtroom workgroup pressures defendants into plea bargains. Prosecutors use evidence strength to induce guilty pleas; judges warn defendants that conviction at trial will bring harsher sentences; defense attorneys (worried about being paid and about uncertainty) urge clients to accept deals.

Statistics: 90% of felonies and 98% of misdemeanors are resolved by plea bargain. This raises questions about whether the U.S. adversarial system is actually adversarial, or simply a system of negotiated settlements.

The same dynamic occurs in civil cases: the vast majority settle before trial.