The Dormant Commerce Clause
Congress's commerce power has a shadow: even when Congress is silent, states can't discriminate against or unduly burden interstate commerce. One sorting question decides nearly every problem.
The DCC analysis
A state law touches interstate commerce
And Congress hasn't spoken.
Does the law discriminate against out-of-staters—on its face, in purpose, or in effect?
Virtually per se invalid. Survives only if it's the least discriminatory way to serve a legitimate local purpose (Maine v. Taylor's parasite-free fish—the rare survivor).
Is the burden on interstate commerce clearly excessive compared to the local benefits?
Unconstitutional under Pike balancing.
Constitutional
Evenhanded laws with proportionate burdens survive.
What counts as discrimination
| Flavor | What it looks like | 🐚 Example |
|---|---|---|
| Facial | The text itself treats out-of-staters worse | “Only State A salsa may be sold at the state fair”—Rosa's out-of-state jars are banned by name |
| Purpose | Neutral words, protectionist goal | The “local freshness” rule enacted after Liv's out-of-state bakery took half the market |
| Effect | Neutral words, but the burden lands on outsiders | Requiring all melons sold in-state to be packed in-state—hollowing out Noodle's out-of-state packing plant |
Hoarding and dumping both count: keeping resources in (in-state-only sales) and keeping problems out (banning out-of-state waste) are equally protectionist. So are forced local-processing rules (Dean Milk, Carbone).
Evenhanded laws: Pike balancing
A nondiscriminatory law regulating evenhandedly is valid unless the burden on interstate commerce is clearly excessive in relation to the putative local benefits. Weigh compliance costs, disruption of uniform national markets, and whether less burdensome alternatives exist.
State A requires biometric verification for large transfers; complying costs Liv's multistate bank $50 million to reprogram its national system, while the security benefits are disputed. Evenhanded—so it's Pike: a $50M burden against thin, contested benefits is a real fight (this is the July 2017 MEE, worked in full below).
The escape hatches
Market participant: when the state buys, sells, or hires rather than regulates, it may favor its own—a state-owned cement plant can sell to residents first (Reeves v. Stake). The exception doesn't reach “downstream” conditions on later resale (South-Central Timber).
Congressional consent: Congress can bless state discrimination the DCC would otherwise forbid—the dormant doctrine only fills silence.
Traditional government functions: favoring the state's own public waste facility survives where favoring a private one wouldn't (United Haulers).
State A's own hydro plant sells cheap power to residents first—market participant, fine. State A orders private utilities to prefer residents—regulation, back to the DCC, presumptively invalid.
Don't confuse it with Privileges & Immunities
- Protects interstate commerce itself
- Corporations and aliens may sue
- Market-participant exception exists
- Congress can consent to discrimination
- Protects out-of-state citizens' fundamental rights—chiefly earning a living
- Only natural citizens—no corporations, no aliens
- No market-participant exception
- Needs discrimination against outsiders + substantial justification
Exam sorting: a corporation hurt by a neutral-but-burdensome law → DCC only. An individual barred from working by an out-of-stater fee → argue both, but P&I is the sharper fit. If Congress approved the scheme → DCC evaporates; P&I doesn't.
Where the points are
The traps examiners actually set.
- Most tested
- The discriminatory/evenhanded sort; Pike balancing stated precisely (“clearly excessive”); the market-participant exception; DCC vs. P&I plaintiff rules.
- Classic traps
- A corporation suing under P&I (can't); treating any burden as fatal (evenhanded laws usually survive); missing congressional consent in the facts; forgetting discrimination-in-effect; applying the market-participant exception to regulation.
Keep going: Sovereign Immunity & DCC MEE guide Green Energy Act MEE guide Con Law Attack Sequences