Criminal Procedure

Warrant Requirement

The Fourth Amendment’s default rule that searches and seizures require a warrant supported by probable cause. The recognized exceptions (consent, exigent circumstances, search incident to arrest, the automobile exception, plain view) do most of the work in practice, so litigation is usually about whether an exception applies rather than whether the default holds.

Reasonable Expectation of Privacy

The test from Katz v. United States for whether government conduct counts as a search at all: did the person exhibit an expectation of privacy that society accepts as reasonable. Carpenter v. United States extended the idea to digital records held by third parties, and Chatrie applied it to geofence location data in 2026.

Probable Cause and Reasonable Suspicion

The two working standards of street-level criminal procedure. Probable cause, required for arrests and most warrants, means a fair probability based on the facts; reasonable suspicion, the lower Terry standard, means specific and articulable facts suggesting criminal activity, enough for a brief stop but not an arrest.

Stop and Frisk

The Terry v. Ohio doctrine allowing a brief investigative stop on reasonable suspicion and a limited pat-down for weapons if the officer reasonably suspects the person is armed and dangerous. The frisk is a weapons check, and evidence of its limits shows up whenever a pat-down turns into a full search.

Exclusionary Rule

The remedy that makes the other rules matter: evidence obtained in violation of the Fourth Amendment is generally inadmissible, a rule applied to the states in Mapp v. Ohio. It is a judicially created deterrent rather than a constitutional command, which is why the Court has carved exceptions like good faith, and the suppression motion is its courtroom vehicle.

Privilege Against Self-Incrimination

The Fifth Amendment right not to be compelled to be a witness against oneself, enforced through the Miranda framework: warnings are required before custodial interrogation, and the two triggers are custody and interrogation. Statements taken in violation are generally excluded from the prosecution’s case.

Right to Counsel and to a Jury

The Sixth Amendment pair that structures the trial itself. Gideon v. Wainwright requires appointed counsel for indigent defendants facing incarceration, Duncan v. Louisiana incorporated the jury right against the states, and the contours are still moving: Villarreal defined what counsel may discuss mid-testimony in 2026, and Kian v. Florida, awaiting argument, asks whether the jury must have twelve members.

Part 1: Work the Scenarios

Copy the Encounter Analyzer into a fresh chat and work through the six scenarios below, one at a time. For each, record the governing amendment, the standard the government must meet, the likely outcome on these facts, and the remedy if the government loses. Then verify each conclusion against the Oyez summary, the Constitution Annotated, or the opinion itself, and note every place the model hedged, missed a controlling case, or stated the rule too broadly.

Scenario 1. Acting on an anonymous call reporting a man with a gun, an officer stops a man matching the description on a public sidewalk and pats down his outer clothing.

Scenario 2. During a routine stop for a broken taillight, the officer finishes writing the ticket, then holds the driver eight more minutes so a drug dog can arrive and circle the car.

Scenario 3. Investigating a robbery, detectives ask Google for a list of every device present within a block of the scene during a one-hour window, without seeking a warrant.

Scenario 4. Detectives question a suspect for two hours in a closed interview room at the station without Miranda warnings, having told him once at the start that he is free to leave.

Scenario 5. A defendant charged with a misdemeanor that carries possible jail time tells the judge he cannot afford a lawyer and is told to proceed on his own.

Scenario 6. Midway through a defendant’s testimony, the judge recesses trial overnight and orders him not to discuss his ongoing testimony with his attorney until he retakes the stand.

Part 2: Build a Doctrine Timeline

Choose one right to trace in depth: search and seizure, self-incrimination, right to counsel, or trial by jury. Run the Doctrine Timeline Builder and verify every entry it produces, starting with the two entries the model itself flags as most likely to be wrong. Correct what needs correcting and keep notes on what the model got wrong and why the error was believable.

Part 3: Track a Live Dispute

Run the Tech Dispute Tracker and pick one current fight over investigative technology. Confirm through your own searching that the dispute is real and fairly described, and read at least one of the sources the model cites. The point is a working picture of where Fourth Amendment doctrine is moving right now, after Carpenter and Chatrie.

Part 4: Write Your Post

Write a 400–600 word post with three components. A scenario table covering all six scenarios: the right at stake, the standard, your verified conclusion, and the source you checked it against. A full prose analysis of the one scenario you found hardest, walking through the doctrine step by step. A closing paragraph covering the errors you caught the model making across all three parts and a 3–4 sentence account of the live dispute you tracked.

Part 5: Share Chat Link

Include one AI chat link with a 1–2 sentence explanation of what the conversation shows and why you chose to share it.

The Encounter Analyzer

You are a criminal procedure tutor for a college constitutional law student. I will paste one police-encounter scenario at a time. For each scenario, work step by step rather than announcing a conclusion: identify the governing amendment and the specific right at stake, name the controlling doctrine and the leading Supreme Court case that established it, state the standard the government must meet, apply that standard to the facts I gave you, and say what remedy a court would consider if the government’s action falls short. Where the outcome depends on a fact the scenario does not state, name the missing fact explicitly and explain how each version of it would change the result. End every analysis by naming the single best source for me to confirm the rule you applied: the Oyez page for the controlling case, the relevant Constitution Annotated essay, or the opinion itself. Ask me for my first scenario.

This prompt uses decomposition and missing-fact elicitation: forcing the model to reason in ordered steps and to name what it does not know produces analysis you can actually check, and the closing instruction builds verification into every exchange rather than leaving it optional.

The Doctrine Timeline Builder

You are a constitutional criminal procedure researcher. Begin by asking me which right I want to trace: search and seizure under the Fourth Amendment, self-incrimination under the Fifth, right to counsel under the Sixth, or trial by jury under the Sixth. Then build a chronological timeline of the Supreme Court cases that shaped that right, from the earliest significant decision to the present, giving each entry the case name, the year, a two-sentence statement of the holding, and one sentence on how it changed what came before. Flag any entry where you are uncertain about the year, the holding, or the sequence instead of presenting it with false confidence, because I will verify every entry against authoritative sources before relying on it. End by naming the two entries in your own timeline you consider most likely to contain an error and why.

The announced-verification technique changes the model’s behavior: telling it every claim will be checked, and requiring it to flag its own uncertainty and nominate its likeliest errors, surfaces the doubt models usually hide. The self-nominated error candidates become your triage list, which is responsible AI use built into the prompt itself.

The Tech Dispute Tracker

You are a legal research assistant tracking Fourth Amendment disputes over investigative technology. Begin by asking me which technology I want to explore: geofence warrants after Chatrie v. United States, facial recognition, automated license plate readers, cell-site simulators, or another I name. Then use your web search tool to find one live dispute from the past two years involving that technology: a pending case, a new statute, or an agency policy fight. Explain who the parties are, what the Fourth Amendment question is, and how Carpenter v. United States and Chatrie bear on it. Cite the sources you relied on so I can confirm the dispute is real and fairly described, and keep what your sources establish clearly separated from your own analysis of where the doctrine is heading.

Grounding the model in live search with required citations keeps it out of its training data, where recent legal developments are least reliable, and the instruction to separate sourced fact from analysis exposes the seam you most need to verify.