Erie Doctrine — Apply Erie doctrine - Bar Exam Uniform

SECTION 1

Historical Context & Motivation

The question of which law a federal court should apply when hearing a case based on diversity of citizenship jurisdiction has been one of the most consequential issues in American civil procedure. For nearly a century after the founding of the Republic, federal courts operated under the assumption that a body of general federal common law existed alongside state law, permitting federal judges to disregard state court decisions on matters of general jurisprudence. This regime, sanctioned by the Supreme Court in Swift v. Tyson (1842), generated profound inequities: a litigant's rights could depend entirely on whether the case was filed in state or federal court, encouraging rampant forum shopping and creating the inequitable administration of the laws that the Erie doctrine was ultimately designed to eradicate.

1842 • Swift v. Tyson

Justice Story held that the Rules of Decision Act required federal courts to follow state statutory law but not state judicial decisions on matters of 'general law,' creating a body of independent federal common law in diversity cases.

1938 • Erie Railroad Co. v. Tompkins

Justice Brandeis overruled Swift, declaring there is no federal general common law and that federal courts exercising diversity jurisdiction must apply the substantive law of the state in which they sit, including state judicial decisions.

1945 • Guaranty Trust Co. v. York

The Court developed the 'outcome-determinative' test: if applying a different rule in federal court would substantially affect the outcome of the litigation, the state rule must be applied.

1958 • Byrd v. Blue Ridge Rural Electric Cooperative

The Court introduced a balancing test, weighing the state interest behind its rule against countervailing federal interests, particularly the Seventh Amendment right to jury trial, refining the pure outcome-determinative approach.

1965 • Hanna v. Plumer

The Court established a bifurcated framework: if a valid Federal Rule of Civil Procedure controls the issue, the Supremacy Clause compels its application; if no Federal Rule applies, the modified outcome-determinative test (twin aims of Erie) governs.

The central question that the Erie doctrine addresses is deceptively simple: When a federal court sits in diversity, should it apply state law or federal law to a particular issue? The answer, refined over decades of Supreme Court jurisprudence, depends on a careful analytical framework that distinguishes between substantive and procedural rules, examines the source of the competing federal rule, and evaluates the constitutional and policy implications of each choice. Mastering this framework is essential for any bar examination candidate.

SECTION 2

Core Principles & Definitions

The Erie doctrine rests on a series of interrelated constitutional, statutory, and policy principles. Understanding these foundations is critical because the doctrine is not a single rule but rather a multi-layered analytical framework that requires identifying the nature of the competing rules and selecting the appropriate test. The following core principles form the doctrinal architecture that every law student must internalize.

No Federal General Common Law

Erie's foundational holding: except in areas governed by the federal Constitution or federal statutes, there is no general federal common law. Federal courts in diversity cases must apply state substantive law, including state court decisions, not merely state statutes.

Substance vs. Procedure Distinction

Federal courts apply state substantive law but retain the authority to apply federal procedural law. The characterization of a rule as 'substantive' or 'procedural' is context-dependent and determined through the applicable Erie test, not by formalistic labels.

Twin Aims of Erie

As articulated in Hanna v. Plumer, Erie's twin aims are (1) discouraging forum shopping between state and federal court, and (2) avoiding the inequitable administration of the laws—ensuring that the outcome of litigation does not turn on the choice of forum.

The Rules of Decision Act

28 U.S.C. § 1652 provides that the laws of the several states shall be regarded as rules of decision in federal civil actions, except where the Constitution, treaties, or federal statutes otherwise require or provide. Erie interprets this Act.

The Rules Enabling Act

28 U.S.C. § 2072 authorizes the Supreme Court to promulgate Federal Rules of Civil Procedure that govern practice and procedure in federal courts. These rules are valid so long as they do not abridge, enlarge, or modify any substantive right.

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KEY TAKEAWAY

Think of a federal court sitting in diversity as a guest in the state's legal house. The guest follows the house rules on matters that define the parties' rights and obligations (substantive law) but brings its own operating procedures for how it runs its courtroom (procedural law). The Erie analysis is essentially about determining which category a particular rule falls into—and choosing the correct test depends on what type of federal authority is being asserted.

SECTION 3

The Erie Decision Tree — Visual Framework

The most effective way to apply the Erie doctrine on a bar examination is to follow a structured decision tree. The analysis begins with one threshold question: Is there a valid federal directive—a Federal Rule of Civil Procedure, a federal statute, or a constitutional provision—that directly conflicts with the state rule at issue? If so, the analysis proceeds down one branch. If not, it proceeds down another. The following flowchart illustrates this bifurcated framework.

This decision tree illustrates the two-track Hanna framework. The left branch applies when a Federal Rule of Civil Procedure or federal statute is on point and directly conflicts with state law (Hanna prong one). The right branch applies the unguided Erie analysis (Hanna prong two), using the twin aims test and, where applicable, Byrd balancing.

As the diagram illustrates, the analysis is fundamentally bifurcated. On the left branch, the existence of a Federal Rule that directly conflicts with the state rule triggers a validity inquiry under the Rules Enabling Act: if the Federal Rule is "arguably procedural" and does not abridge, enlarge, or modify substantive rights, the federal court applies the Federal Rule under the Supremacy Clause. On the right branch, where no Federal Rule is on point, the court engages in a more nuanced analysis, asking whether applying a different rule in federal court would encourage forum shopping or lead to the inequitable administration of the laws. The Byrd balancing test may also apply when there is a countervailing federal interest at stake, such as the allocation of functions between judge and jury.

SECTION 4

The Three Erie Tests in Detail

The Erie doctrine has evolved through a series of landmark decisions, each contributing a distinct analytical test. Although these tests are sometimes discussed as competitors, modern Erie analysis integrates them into a coherent framework. The three primary tests are the outcome-determinative test from Guaranty Trust, the Byrd balancing test, and the Hanna two-prong framework. Understanding when and how to deploy each test is the key to applying Erie correctly on the bar examination.

Test 1: Outcome-Determinative Test (Guaranty Trust v. York, 1945)

The outcome-determinative test asks whether the choice between the state rule and the federal rule would significantly affect the outcome of the litigation. If applying the federal practice instead of the state rule would lead a reasonable litigant to choose federal court over state court for that reason alone, then the state rule is "substantive" for Erie purposes and must be applied. In Guaranty Trust, the issue was whether a state statute of limitations applied in a federal equity action. The Court held that it did, because applying a different limitations period in federal court would materially affect the result—a plaintiff time-barred in state court could simply re-file in federal court. However, taken to its extreme, this test would swallow all procedural rules, since virtually any procedural difference could theoretically alter outcomes. Later cases therefore refined this test.

Test 2: Byrd Balancing Test (Byrd v. Blue Ridge, 1958)

The Byrd balancing test tempers the outcome-determinative approach by introducing a weighing analysis. The court considers three factors: (1) whether the state rule is "bound up" with state-created rights and obligations, or merely a form and mode of enforcing those rights; (2) countervailing federal interests, such as the federal policy favoring jury determination of factual issues under the Seventh Amendment; and (3) the likelihood that applying the federal practice would actually lead to a different outcome. In Byrd, the state rule assigned a factual issue to the judge, but the federal court held that the Seventh Amendment interest in jury trial outweighed the state's procedural preference because the state rule was not bound up with the definition of state substantive rights.

Test 3: Hanna Two-Prong Framework (Hanna v. Plumer, 1965)

The Hanna framework synthesizes the prior case law into a workable two-prong structure that governs modern Erie analysis. Under Hanna prong one, when a Federal Rule of Civil Procedure is on point and directly conflicts with the state rule, the court applies the Federal Rule if it is valid under the Rules Enabling Act—meaning it is "arguably procedural" and does not abridge, enlarge, or modify any substantive right. The Supreme Court has never invalidated a Federal Rule on this basis. Under Hanna prong two (sometimes called the "relatively unguided Erie choice"), where no Federal Rule is directly on point, the court applies a modified outcome-determinative test focused on the twin aims: would applying the federal practice encourage forum shopping, and would it lead to the inequitable administration of the laws? If the answer to either question is yes, state law applies. The Byrd balancing factors may also be considered in this analysis.

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SHADY GROVE PRECISION

In Shady Grove Orthopedic Associates v. Allstate Insurance Co. (2010), the Court addressed what constitutes a "direct conflict" between a Federal Rule and state law. The plurality held that FRCP 23 (class actions) "answered the question" whether a suit could proceed as a class action, directly conflicting with a New York statute prohibiting class actions for certain penalty claims. This case underscores that the threshold inquiry—whether the Federal Rule is "sufficiently broad to control the issue"—is itself contested and requires careful analysis.

SECTION 5

Substance vs. Procedure — Classification Guide

One of the most challenging aspects of applying the Erie doctrine is classifying a particular rule as "substantive" or "procedural." The Supreme Court has cautioned that these labels are not fixed categories but are instead functional characterizations that depend on context. A rule that is procedural for one purpose may be substantive for Erie purposes. The following table synthesizes the key classifications established by Supreme Court precedent.

Legal Issue	Classification	Controlling Case
Statutes of limitations	Substantive — apply state law	Guaranty Trust v. York
Burden of proof	Substantive — apply state law	Cities Service Oil Co. v. Dunlap
Elements of a cause of action	Substantive — apply state law	Erie Railroad Co. v. Tompkins
Choice-of-law rules	Substantive — apply state law	Klaxon Co. v. Stentor Electric
Service of process method	Procedural — apply federal rule (FRCP 4)	Hanna v. Plumer
Judge vs. jury allocation of fact issues	Procedural — may apply federal practice	Byrd v. Blue Ridge
Class action availability	Procedural — apply FRCP 23	Shady Grove v. Allstate
Door-closing statutes (forum restrictions)	Substantive — apply state law	Woods v. Interstate Realty Co.

Key substance-procedure classifications under Erie doctrine

The substance-procedure spectrum shows that rules are not rigidly classified but exist along a continuum. Rules on the far left are clearly substantive and governed by state law. Rules on the far right are clearly procedural and governed by Federal Rules. The gray zone in the middle requires the most careful Erie analysis.

SECTION 6

Worked Example — Applying the Erie Framework

Consider the following hypothetical, modeled on a typical bar examination question: A citizen of State A sues a citizen of State B in federal district court in State B, asserting a state-law negligence claim with damages exceeding $75,000. State B requires that in personal injury actions, the plaintiff must file an expert affidavit with the complaint attesting to the merit of the claim. No Federal Rule of Civil Procedure imposes such a requirement. The defendant moves to dismiss for failure to comply with the state expert-affidavit rule. Should the federal court apply the State B requirement?

Erie Analysis: State Expert-Affidavit Requirement

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Step 1 — Confirm Diversity Jurisdiction and Erie Applicability

The case involves a state-law negligence claim between citizens of different states with more than $75,000 in controversy. The federal court has diversity jurisdiction under 28 U.S.C. § 1332. Because the court is exercising diversity jurisdiction over a state-law claim, the Erie doctrine applies. The court must determine whether to apply state or federal law to the expert-affidavit requirement.

Erie applies — diversity jurisdiction over a state-law claim.
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Step 2 — Identify the Threshold Question: Is There a Federal Rule on Point?

Ask whether any Federal Rule of Civil Procedure, federal statute, or constitutional provision directly addresses the same issue as the state rule. Here, the state rule requires an expert affidavit at the complaint stage. FRCP 8(a) governs the general requirements of a complaint (short and plain statement of the claim), and FRCP 9 addresses certain matters requiring specificity, but neither directly addresses expert-affidavit requirements. FRCP 26(a)(2) governs expert disclosures but operates at the discovery stage, not at the pleading stage. There is no Federal Rule that directly conflicts with the state expert-affidavit requirement.

No Federal Rule directly on point → proceed to Hanna prong two (unguided Erie analysis).
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Step 3 — Apply the Twin Aims Test

Under Hanna prong two, ask whether failing to apply the state rule would (1) encourage forum shopping, or (2) lead to the inequitable administration of the laws. Forum shopping: If the federal court does not require the expert affidavit, a plaintiff with a potentially frivolous claim might prefer federal court precisely to avoid the state's screening mechanism. This differential treatment between state and federal court in the same state would encourage forum shopping. Inequitable administration: A plaintiff who cannot satisfy the state's expert-affidavit requirement would be barred in state court but free to proceed in federal court, producing a fundamentally inequitable result where outcomes depend on forum choice rather than the merits.

Both twin aims are implicated — disregarding the state rule would encourage forum shopping and inequitable administration.
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Step 4 — Consider Byrd Balancing (If Applicable)

Is the state rule 'bound up' with state substantive rights? The expert-affidavit requirement is designed to screen frivolous medical malpractice or personal injury claims—it reflects a substantive policy judgment about the conditions under which such claims may proceed. It is not merely a 'form and mode' of enforcement but is intertwined with the state's regulation of tort litigation. Furthermore, there is no strong countervailing federal interest comparable to the Seventh Amendment interest in Byrd. The federal system has no analogous policy requiring that unscreened personal injury claims proceed past the complaint stage.

Byrd balancing favors applying state law — state rule is bound up with substantive policy, no countervailing federal interest.
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Step 5 — Conclusion

The federal court should apply State B's expert-affidavit requirement. No Federal Rule directly conflicts with the state rule, so Hanna prong two governs. Both of Erie's twin aims support applying the state rule: failure to do so would encourage forum shopping and create inequitable outcomes. The Byrd balancing factors also favor the state rule because it is bound up with the state's substantive regulation of personal injury litigation and no countervailing federal interest overrides it.

Apply state law — the expert-affidavit requirement must be followed in federal court.

SECTION 7

Comparing the Erie Tests — Strengths & Limitations

Each of the three Erie tests offers a distinct analytical lens, and no single test perfectly resolves every case. Understanding the strengths and limitations of each approach helps you select the correct analytical framework and anticipate how bar examiners may test the doctrine. The following table provides a comparative overview.

Test	Strengths	Limitations
Outcome-Determinative (Guaranty Trust)	Simple and intuitive; directly addresses the problem of forum shopping by focusing on whether the choice of law changes the result.	Over-inclusive — virtually any procedural difference could theoretically affect outcomes, potentially requiring federal courts to apply all state rules.
Byrd Balancing	Provides nuance by weighing competing interests; preserves important federal interests (e.g., jury trial right); avoids the over-breadth of the pure outcome-determinative test.	Relatively indeterminate; balancing tests produce less predictable results; the Court has rarely applied this test outside the judge/jury allocation context.
Hanna Two-Prong Framework	Clear, structured analysis; separates FRCP conflicts from unguided choices; incorporates the twin aims for policy guidance; most widely tested on the bar exam.	Threshold question of 'direct conflict' can itself be contested (see Shady Grove); the REA validity analysis is largely toothless since no Federal Rule has ever been invalidated.

Comparative analysis of the three primary Erie tests

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BAR EXAM STRATEGY

On the bar exam, think of Erie analysis as a triage protocol. Just as an emergency physician first checks for the most critical condition before moving to secondary assessments, your Erie analysis should first check whether a Federal Rule is directly on point (Hanna prong one). If yes, validate the rule under the REA and apply it. Only if no Federal Rule governs do you proceed to the unguided Erie choice (Hanna prong two), where you apply the twin aims test and, if necessary, Byrd balancing. This sequenced approach prevents you from wasting analysis on the wrong test.

SECTION 8

Advanced Erie Issues & Modern Developments

The Erie doctrine continues to generate significant scholarly debate and judicial refinement. Several advanced issues appear on bar examinations and in practice, requiring students to extend the basic framework to more complex scenarios. This section addresses the most important of these advanced topics, including federal common law exceptions, the reverse-Erie doctrine, and the continuing tension in cases like Gasperini and Shady Grove.

Issue	Basic Erie Analysis	Advanced Consideration
Federal Common Law Exceptions	Erie holds there is no general federal common law.	Federal common law survives in specific enclaves: admiralty, interstate disputes, suits implicating uniquely federal interests (e.g., government contracts under Boyle v. United Technologies). Erie does not apply in these areas.
Determining State Law	Federal courts apply the substantive law of the state in which they sit.	When the state's highest court has not addressed the issue, federal courts must predict how it would rule, considering lower state court decisions, dicta, trends in other jurisdictions, and scholarly commentary. Some federal courts may also certify the question to the state's highest court.
Reverse-Erie Doctrine	Erie governs what law federal courts apply.	The reverse-Erie doctrine (from Dice v. Akron, Canton & Youngstown R.R.) asks when state courts must apply federal procedural rules in cases governed by federal substantive law—for example, state courts hearing FELA claims must allow jury trial on the issue of negligence.
Gasperini v. Center for Humanities (1996)	Standard Hanna analysis would seem to apply.	The Court adopted a hybrid approach: state law (NY's standard for reviewing excessive verdicts) applied at the trial level, but the federal standard of review (abuse of discretion) applied at the appellate level, accommodating both Erie and the Seventh Amendment's Re-examination Clause.

Basic vs. advanced Erie issues

These advanced issues demonstrate that the Erie doctrine, despite its apparently clear framework, remains a site of significant judicial creativity and doctrinal tension. Bar examiners occasionally test these nuances, so awareness of federal common law enclaves, the certification process, and the hybrid approach of Gasperini can distinguish a strong answer from a merely competent one. The core analytical skill, however, remains the same: identify the competing rules, determine whether a valid Federal Rule is on point, and apply the correct test methodically.

SECTION 9

Practice Problems

Question 1: CONCEPTUAL

Explain the constitutional basis for the Erie doctrine. Why did the Supreme Court in Erie conclude that applying 'general federal common law' in diversity cases was unconstitutional, and what specific constitutional provisions support this holding?

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The Erie Court identified two constitutional bases for its holding. First, the Tenth Amendment reserves to the states those powers not delegated to the federal government; because the Constitution does not grant Congress the power to create general substantive rules for areas traditionally governed by state law, federal courts cannot arrogate that power to themselves through the guise of 'general common law.' Second, the Court suggested that Swift's regime violated the Equal Protection principles embedded in the Due Process Clause by allowing federal courts to apply different substantive rules than state courts in the same state, thereby discriminating based on citizenship (since only out-of-state citizens could invoke diversity jurisdiction). Justice Brandeis wrote that Swift permitted 'discrimination by non-citizens against citizens,' fundamentally undermining the constitutional structure of federalism.

Question 2: BASIC APPLICATION

A plaintiff files a diversity action in federal court in State X. State X has a statute requiring plaintiffs in defamation cases to demand a retraction before filing suit. No Federal Rule of Civil Procedure addresses pre-suit retraction demands. The defendant moves to dismiss because the plaintiff did not send a retraction demand. Which Erie track applies, and what is the likely result?

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Because no Federal Rule of Civil Procedure directly addresses pre-suit retraction demands, the analysis proceeds under Hanna prong two (the unguided Erie choice). The court must apply the twin aims test. First, forum shopping: if the federal court does not enforce the retraction-demand requirement, plaintiffs in State X could bypass a mandatory precondition to suit simply by filing in federal court, creating a strong incentive to forum shop. Second, inequitable administration of the laws: the retraction-demand statute reflects State X's substantive policy of encouraging dispute resolution and reducing litigation in defamation cases; ignoring it would produce different litigation outcomes depending solely on the forum chosen. Furthermore, under Byrd analysis, the retraction-demand requirement appears 'bound up' with the state's definition of when a defamation cause of action accrues, and no countervailing federal interest overrides it. The federal court should apply the State X retraction-demand requirement.

Question 3: INTERMEDIATE

A federal court sits in diversity in State Y. State Y requires that complaints in medical malpractice actions be verified (signed under oath). FRCP 11 requires that all pleadings be signed by an attorney certifying that the claims are well-grounded in fact and law, but does not require verification under oath. The plaintiff files an unverified complaint. The defendant argues the complaint should be dismissed under State Y's verification requirement. How should the court analyze this issue under Erie?

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This problem requires determining whether FRCP 11 directly conflicts with the state verification requirement—the threshold question under Hanna. There is a reasonable argument that FRCP 11 is 'sufficiently broad to control the issue' because it specifically addresses the requirements for signing pleadings and the certifications that accompany them. If FRCP 11 directly conflicts with the state rule, Hanna prong one governs: the court asks whether FRCP 11 is valid under the Rules Enabling Act. Because FRCP 11 is 'arguably procedural' (it regulates the manner of filing, not the substance of claims) and has never been invalidated, the federal court would apply FRCP 11 and not require verification. However, if the court concludes that FRCP 11 and the state verification rule address different aspects of pleading (FRCP 11 governs attorney certification while the state rule imposes a separate affirmation requirement on the party), there would be no direct conflict, and the analysis shifts to Hanna prong two. Under the twin aims test, the state verification requirement likely would need to be applied because it serves a screening function that, if ignored, would encourage forum shopping by medical malpractice plaintiffs seeking to avoid the verification burden.

Question 4: APPLIED

A plaintiff files a class action in federal court in State Z under diversity jurisdiction, asserting state-law consumer fraud claims. State Z has a statute providing that penalties under the consumer fraud act 'may not be recovered in a class action.' The defendant argues that FRCP 23 governs class action availability in federal court and that the state restriction should not apply. Analyze the Erie issue, discussing how Shady Grove Orthopedic Associates v. Allstate Insurance Co. informs your analysis.

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This scenario closely parallels Shady Grove. The threshold question is whether FRCP 23 directly conflicts with the state statute. Under the Shady Grove plurality (Justice Scalia), FRCP 23 'answers the question in dispute'—whether a suit may proceed as a class action—because Rule 23 creates a categorical entitlement to class certification if its prerequisites are met. The state statute purports to strip that entitlement for certain claims. Under this reading, the rules directly conflict, placing the analysis under Hanna prong one. FRCP 23 satisfies the Rules Enabling Act because it is 'arguably procedural' (it governs the form of the lawsuit, not the substantive rights at issue), and the Court has never invalidated a Federal Rule. Therefore, FRCP 23 would apply and the class action could proceed. However, Justice Stevens's concurrence in Shady Grove adopted a narrower view, suggesting courts should examine whether the state rule is 'so intertwined with a state right or remedy that it functions to define the scope of the state-created right.' Under this approach, if the State Z statute reflects a substantive limitation on damages (i.e., the state has decided that class-wide penalties are excessive), the state rule might apply even in the face of FRCP 23. The bar examiner may expect discussion of both the plurality and concurrence.

Question 5: CRITICAL THINKING

Some scholars argue that the Erie doctrine has been 'essentially solved' by the Hanna framework, while others contend that fundamental tensions remain unresolved. Evaluate this debate by discussing: (a) whether the 'direct conflict' threshold question creates more problems than it solves; (b) whether the REA validity inquiry is meaningful or merely theoretical; and (c) whether Byrd balancing has any continuing role in modern Erie analysis.

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(a) The 'direct conflict' inquiry is the most contested aspect of modern Erie analysis. Shady Grove exposed deep disagreements: the plurality read Federal Rules broadly (any Rule that 'answers the question' creates a direct conflict), while the concurrence urged a narrower, substance-sensitive reading. If the direct conflict threshold is set too broadly, Hanna prong one becomes a near-automatic path to federal rule supremacy, effectively gutting state substantive policies disguised as procedural requirements. If set too narrowly, the unguided Erie analysis governs most cases, reintroducing the indeterminacy that Hanna sought to eliminate. (b) The REA validity inquiry is largely theoretical. The Supreme Court has never invalidated a Federal Rule under the REA, and the 'arguably procedural' standard is remarkably generous. This means that Hanna prong one effectively functions as a one-way ratchet favoring federal rules, raising concerns that federal procedural uniformity may override legitimate state substantive policies. (c) Byrd balancing retains continuing vitality in the unguided Erie track, particularly when federal structural interests (like jury trial rights) are at stake. However, the Court has rarely invoked Byrd in recent decades, and some commentators view it as subsumed within the twin aims analysis. Its greatest value may be as a safety valve: when rigid application of the outcome-determinative test would compel applying a state rule that fundamentally conflicts with the constitutional structure of federal courts, Byrd permits a more nuanced assessment.

SUMMARY

Erie Doctrine — Summary Review

Summary

The Erie doctrine requires federal courts exercising diversity jurisdiction to apply state substantive law while retaining federal procedural law. The modern framework, established by Hanna v. Plumer, is bifurcated. Under Hanna prong one, when a Federal Rule of Civil Procedure or federal statute directly conflicts with a state rule, the federal directive applies if it is valid under the Rules Enabling Act (i.e., it is arguably procedural and does not abridge substantive rights). Under Hanna prong two, when no Federal Rule is on point, the court applies the twin aims test: would ignoring the state rule encourage forum shopping or produce the inequitable administration of the laws? If so, state law applies.

The Byrd balancing test provides an additional layer of analysis when countervailing federal interests are at stake, weighing the state interest behind its rule against federal interests such as the Seventh Amendment right to jury trial. Key classifications to memorize include: statutes of limitations, burden of proof, and choice-of-law rules are substantive (apply state law), while service of process and class action availability are procedural (apply Federal Rules). On the bar exam, always begin by asking the threshold question, identify which analytical track you are on, and work through the appropriate test methodically.