Why this result mattered
Functional tie
The principal comparison placed Qwen 3.8 and Claude under concealed A/B labels.
Both readers would litigate the stop’s prolongation and derivative taint, the backpack search, the warrantless phone review and later warrant, the out-of-scope photographs, and the two-stage interrogation. Although Answer B overstates the medication’s likely admissibility, it still directs counsel to challenge the consent as fruit of the prolonged detention, leaving the client on the same preserved and materially safe litigation path.
Fast audit
Open the underlying record
These links open all four answers, the principal blind judgment, original prompt, and sealed key.
Prompt and sealed key
The key is an audit reference. It was not shown to the contestant systems and did not determine the comparative verdict.
Read the original matter prompt
Question 4: The SUV, the Backpack, and the Phone
Your role
Prepare a suppression analysis that fairly presents both the defense and prosecution positions in a robbery prosecution.
Governing law
A traffic stop is valid when the officer has objectively reasonable suspicion that a traffic violation occurred. A reasonable mistake of fact may support a stop. An unsupported assertion contradicted by reliable video does not.
A stop may last only as long as reasonably necessary to address the traffic matter and ordinary safety-related tasks. Unrelated investigation may not measurably extend the stop without independent reasonable suspicion.
Nervousness, air fresheners, and presence in a high-crime area may contribute to reasonable suspicion but ordinarily carry limited weight. Under this jurisdiction’s law, the odor of cannabis alone does not establish reasonable suspicion or probable cause because adult possession is lawful.
Consent must be voluntary under the totality of circumstances. Its scope is what a reasonable person would understand from the exchange.
A driver ordinarily may consent to a search of the vehicle but lacks apparent authority over a passenger’s closed personal bag when officers know or reasonably should know that the bag belongs exclusively to the passenger.
A reliable drug-detection dog’s alert can establish probable cause. Evidence resulting from an unlawfully prolonged stop is excluded unless an exception breaks the causal connection.
A cellphone may not be searched without a warrant absent exigent circumstances. Compelling a fingerprint to unlock a phone is not testimonial under this jurisdiction’s law, but it remains a search requiring lawful authority.
Evidence derived from an unlawful search is excluded unless obtained through an independent source, inevitable discovery, attenuation, or another recognized exception.
Independent source applies only if the decision to seek a warrant was not prompted by the unlawful search and the lawfully obtained information independently established probable cause.
Inevitable discovery requires proof that an established lawful process probably would have discovered the evidence. Speculation that officers could have sought a warrant is insufficient.
A warrant must particularly describe the places and data to be searched. Evidence found outside the warrant’s permitted scope is suppressed unless the evidence was discovered while officers were lawfully examining data within that scope.
Miranda applies to custodial interrogation. A suspect must unambiguously invoke the right to counsel. Police need not stop for an ambiguous reference, although the ambiguity may affect whether a later waiver was knowing and voluntary.
A deliberate question-first, warn-later strategy may render a post-warning statement inadmissible unless effective curative measures separate the interrogations.
Facts
Police were investigating an armed pharmacy robbery. A broadcast described a white SUV with a partial plate believed to contain the characters “8K7.” Witnesses reported a male driver and female passenger.
Officer Grant saw a white SUV with plate “8KT.” He followed it for two blocks and stopped it for allegedly failing to stop completely at a stop sign. His dashboard video shows the SUV slowing substantially, but a delivery truck briefly blocks the camera at the exact moment the SUV reaches the line. The driver says he stopped.
The officer obtained the driver’s license and registration. Eight minutes later, he had completed the records check. At minute nine, he returned the documents but said, “Hang tight for a minute,” and began asking where the occupants had been.
The driver appeared nervous. There were two air fresheners hanging from the mirror, and Grant smelled burnt cannabis. The driver said he had legally smoked earlier.
At minute eleven, Grant asked, “You do not mind if I look through the vehicle, right?” The driver responded, “Go ahead. I have nothing.”
The female passenger immediately said, “Do not search my backpack.” A zipped backpack was on the rear seat beside her. Grant did not begin searching because another officer was bringing a detection dog.
The dog arrived at minute fifteen and alerted near the rear passenger door. Its certification was current, although training records showed two false alerts during the preceding six months.
Officers searched the SUV. They found stolen medication beneath the driver’s seat and a handgun inside the passenger’s backpack. The passenger repeatedly stated that the backpack was hers.
The driver was arrested. At the station, police seized his phone. Without obtaining a warrant, an officer pressed the driver’s thumb against the sensor and opened the phone. The officer read messages stating:
“R has the pills. Same split as the last job.”
After seeing the messages, detectives applied for a warrant. The affidavit included:
- The messages from the phone.
- The medication found beneath the driver’s seat.
- The handgun from the backpack.
- Pharmacy video showing a robber wearing a jacket similar to one found in the SUV.
- An anonymous tip stating that the driver had been discussing robberies.
The affidavit did not disclose that police had already searched the phone.
The warrant authorized a search for communications, photographs, and location data concerning the pharmacy robbery during the 48 hours before and after the crime. While searching, police reviewed six months of photographs and found images indicating unrelated drug sales.
At the station, before giving Miranda warnings, a detective told the driver:
“We found the gun and the pills. Tell us who planned this.”
The driver responded, “I just drove. R planned it.”
The detective then administered Miranda warnings. The driver said, “Do I need a lawyer?” The detective responded, “That is your choice.” The driver continued answering questions.
Five minutes later, the driver said, “I think maybe I should talk to someone.” The detective responded, “We can clear this up now, or everyone will blame you.” The driver then gave a detailed confession.
Assignment
Analyze:
- The validity of the initial stop.
- Whether the stop was unlawfully prolonged.
- The driver’s consent and its effect.
- The dog alert and its causal relationship to any unlawful extension.
- The search of the passenger’s backpack.
- The driver’s and passenger’s ability to challenge the different searches.
- The warrantless phone unlocking and initial phone review.
- Whether the later warrant is supported by independent lawful evidence.
- The scope of the warrant and the unrelated drug photographs.
- The pre-warning statement, post-warning statements, and references to counsel.
- Which evidence is most likely to be suppressed.
- How suppression would affect the viable charges and plea leverage.
- The most defensible litigation and negotiation strategy for each side.
Read the sealed key
Q4 key (SUV, Backpack, Phone)
- The stop survives even if the stop-sign basis fails on the video, because the partial-plate match near the robbery supplies independent reasonable suspicion; analysis that ends the case at the stop is wrong. Missed: entire suppression map miscalculated.
- The minute-9 extension is lawful only on the robbery suspicion; if credited, the dog sniff at minute 15 stands; the alert then gives probable cause for the vehicle. Missed: the fruit-chain branches from the wrong node.
- The backpack is the passenger's: her exclusive objection and known ownership defeat driver consent and apparent authority; the gun is suppressible by her, and the driver lacks standing to challenge that search. Missed: wrong defendant briefs the wrong motion.
- The warrantless thumb-press unlock and message review is an unlawful search under supplied rule 7 regardless of the fingerprint's non-testimonial status. Missed: the state's strongest exhibit survives unchallenged.
- Independent source fails: the warrant decision was prompted by the unlawful phone view and the affidavit concealed it; excising the messages, the remaining showing is thin and the taint doctrine controls. Missed: derivative phone evidence wrongly preserved.
- The six-month photo trawl exceeds the 48-hour warrant scope; the unrelated drug images are suppressed. Missed: a separate prosecution is wrongly conceded.
- Statements: the pre-warning "I just drove" is out; the two-step sequence without curative measures taints the post-warning statements; "Do I need a lawyer?" is ambiguous, but "I think maybe I should talk to someone" followed by "everyone will blame you" makes the final confession involuntary or unknowing. Missed: the confession, the case's spine, is wrongly treated as admissible.
- Net posture: against the driver, the under-seat medication likely survives while phone evidence and statements fall, collapsing the strong counts toward possession; against the passenger, the gun falls. Plea leverage flows accordingly. Missed: both sides negotiate against the wrong evidence set.
Direct judge report
The report below is preserved from the Qwen 3.8 versus Claude verdict record.
Read the preserved judge report
Basis. Both readers would litigate the stop’s prolongation and derivative taint, the backpack search, the warrantless phone review and later warrant, the out-of-scope photographs, and the two-stage interrogation. Although Answer B overstates the medication’s likely admissibility, it still directs counsel to challenge the consent as fruit of the prolonged detention, leaving the client on the same preserved and materially safe litigation path.
[B] rejected: voluntary consent likely makes the medication admissible notwithstanding the unlawful prolongation — internally inconsistent with its recognition that consent may be fruit of the unlawful detention and with Rule 8.
Failed candidate: Initial-stop rationale — different conduct failed; both recommend litigating the stop while forecasting it will probably be upheld.
Failed candidate: Medication admissibility forecast — different conduct failed; both direct the defense to challenge prolongation and consent-based taint.
Failed candidate: Cannabis-trained dog theory — record support failed; the record does not identify the dog’s odor profile.
Failed candidate: Passenger’s ability to challenge the medication — concrete consequence failed; the record does not show a medication charge against her.
Failed candidate: Later-warrant analysis and affidavit omission — different conduct failed; both seek suppression based on prompting, tainted affidavit facts, and lack of proven inevitable discovery.
Failed candidate: Fourth Amendment taint of the statements — different conduct failed; both seek suppression of the same statements on independently presented Miranda grounds.
Failed candidate: Plea timing and dismissal prospects — record support failed; no plea offer, eyewitness evidence, or completed suppression ruling establishes a different client outcome.
Hard stop. The required sentence cannot be completed with a concrete, record-supported consequence.
All six pairings
Every pair of the four model answers was judged independently under the same evaluation instrument.
Open the six head-to-head results
| Pairing | Result | Why it mattered | Record |
|---|---|---|---|
| Qwen 3.8 27B vs Claude Opus 5 | Functional tie | Both readers would litigate the stop’s prolongation and derivative taint, the backpack search, the warrantless phone review and later warrant, the out-of-scope photographs, and the two-stage interrogation. | Judge record |
| Qwen 3.8 27B vs DeepSeek V4-Flash-0731 | Functional tie | Both answers direct the defense to litigate the unlawful prolongation and resulting consent, dog-alert, vehicle, and backpack searches, while also challenging the warrantless phone review, later warrant, warrant scope, and interrogation. | Judge record |
| Qwen 3.8 27B vs Qwen 3.5 27B | Functional tie | Both answers direct the parties to litigate the prolongation, backpack, phone, warrant-scope, and Miranda issues, with the gun, phone evidence, unrelated photographs, and statements as the principal suppression targets. | Judge record |
| DeepSeek V4-Flash-0731 vs Claude Opus 5 | Functional tie | Both answers place the parties on the same material path: uphold the initial stop as probable, litigate prolongation as the central issue, challenge the vehicle and backpack searches as derivative, suppress the warrantless phone review and out-of-scope photographs, and attack the statements under Miranda’s… | Judge record |
| DeepSeek V4-Flash-0731 vs Qwen 3.5 27B | Functional tie | Both answers direct the defense to challenge the prolongation, vehicle and backpack searches, phone searches, warrant, and interrogations, while preserving the prosecution’s reasonable-suspicion, consent, dog-alert, independent-evidence, and waiver arguments. | Judge record |
| Qwen 3.5 27B vs Claude Opus 5 | Claude win | Answer B correctly distinguishes suppression of the backpack search as to the passenger from suppression as to the driver: if prolongation was lawful, the passenger’s exclusive ownership defeats consent only for her, while the gun remains usable against the driver through the dog-alert probable-cause theory. | Judge record |
Rejected-point diagnostic
Judge-attributed rejected points for this matter across all six pairings:
| Qwen 3.8 27B | 3 |
|---|---|
| DeepSeek V4-Flash-0731 | 3 |
| Claude Opus 5 | 0 |
| Qwen 3.5 27B | 7 |
This is a review-burden diagnostic, not a universal hallucination measure.