Being stopped by the police can be a nerve-wracking experience. When you see those blue lights flashing behind you, your first thought might be, “how long is this going to take?” But a more important question is: how long are the police legally allowed to keep me?
Most people don’t realize that the U.S. Constitution and Tennessee law places strict limits on how long an officer can detain you during a traffic stop or street encounter. Whether you’re pulled over for speeding or approached by police while walking, knowing your rights can protect you from an unlawful detention or worse—an illegal search or arrest.
In this article, we’ll explain how long the police can legally detain you, when they’re allowed to extend a stop, and what signs indicate you’ve moved from detention to arrest. If you’ve been charged after a questionable stop, it’s important to understand your rights and to speak with an experienced criminal defense attorney right away.
Detained or Arrested? Understanding Terry Stops
When police stop you—whether during a traffic stop or on the street—you’re often in what’s legally called a Terry stop, named after the U.S. Supreme Court case Terry v. Ohio (1968).
A Terry stop is a brief, investigative detention based on reasonable suspicion—a legal standard that requires more than a hunch but less than probable cause. Officers must be able to point to specific facts that suggest you may be involved in criminal activity.
Examples of Terry Stops:
- A police officer sees you swerving while driving and pulls you over—that’s a Terry stop.
- An officer sees someone pacing in front of a closed business late at night, checking door handles—they may stop and question the person based on reasonable suspicion of attempted burglary.
- Police observe someone exiting a known drug house and engaging in a quick hand-to-hand exchange—they may stop and question the person for suspected drug activity.
These stops are temporary and narrow in scope. Police can ask limited questions and may conduct a quick pat-down if they suspect you’re armed. But they can’t hold you indefinitely or start fishing for unrelated offenses without new legal justification.
What a Terry Stop Is Not
Many people confuse being detained with being arrested—but they involve very different legal standards and rights:
- Detained means you’re temporarily held for investigation. You’re not free to leave, but you haven’t been taken into full custody.
- Arrested means you’re officially in custody—typically handcuffed or transported, and the officers must have probable cause to believe you’ve committed a crime.
In other words, all arrests are detentions, but not all detentions are arrests.
A Terry stop falls in between a casual encounter and a full-blown arrest. It’s not an arrest, so police don’t need probable cause—yet. But it’s also not voluntary; if you’re being detained under Terry, you are not free to walk away until the officer completes their investigation.
How Long Can a Traffic Stop Last?
A traffic stop might feel like it takes forever—especially if you’re sitting on the side of the road while the officer runs your license. But legally speaking, police can only detain you as long as it reasonably takes to handle the reason they pulled you over.
This principle was made clear by the U.S. Supreme Court in Rodriguez v. United States (2015), which held that police cannot prolong a stop beyond the time needed to address the original traffic violation, unless they have new, independent grounds for suspicion.
So, what does that mean in practice? Let’s take an example where you’ve been stopped for speeding. The officer can:
- Ask for your license, registration, and proof of insurance,
- Run your information through the system,
- Write you a ticket or issue a warning.
This should take only as long as necessary to complete those tasks—typically a matter of minutes. Once that purpose is complete, the officer must let you go, unless something new gives them legal grounds to continue the detention.
When a Legal Stop Becomes Illegal
If the officer starts asking unrelated questions, delays returning your documents, or calls for a K-9 unit without any new suspicion, the stop may cross the line into an unlawful detention.
For example:
- If you’re pulled over for a broken taillight and the officer spends 25 minutes questioning you about drugs—with no evidence or reason to suspect drug activity—that likely violates your rights.
- If a drug dog is brought to the scene but arrives after the officer has already handled the traffic violation, any evidence found may be inadmissible in court under Rodriguez.
Tennessee courts follow the same rule. Officers must work diligently to complete the purpose of the stop and can’t create unnecessary delays just to look for additional reasons to search or arrest you.
When Can Police Extend the Stop?
While police can’t hold you longer than necessary just because they want to, there are specific situations where they can legally extend a traffic stop. The key is whether something happens during the stop that gives the officer new, independent reasonable suspicion of criminal activity.
1. Development of New Reasonable Suspicion
If, during the course of the stop, the officer observes something unusual or suspicious, they may be legally justified in extending the detention.
Examples:
- The officer smells marijuana or alcohol coming from the car.
- You give inconsistent or nervous answers to basic questions.
- There’s contraband in plain view (e.g., open beer cans, drug paraphernalia).
These observations can shift the stop from a simple traffic investigation to something more serious — and may legally justify further questioning, a pat-down, or a call for backup.
Extending a Stop Through Field Sobriety Tests
An officer cannot automatically conduct SFST’s. An officer needs reasonable suspicion of DUI to prolong the stop because a stop is presumed to be cite-and-release. This means an officer should write a traffic citation unless additional evidence is obtained.
This is the most common legal defense our DUI defense attorneys argue as officers cannot simply extend a stop to conduct standardized field sobriety tests due to evidence of potential consumption. Our attorneys analyze DUI cases to allege that the officer only had reasonable suspicion of consumption, not impairment which would not be sufficient to extend the stop to conduct field sobriety tests. Officers must have evidence of impairment such as admission of a large volume of alcohol, slurred speech, swaying and unsteadiness on feet. Driving behavior should be discussed with the motorist to determine if they were on their phone or a distraction caused the poor driving, rather than simply the odor of alcohol alone being enough for an officer to extend the stop.
Additionally, the reason for any delay becomes very important as officers cannot wait 20-30 minutes for another officer to arrive to conduct SFST’s when they are fully capable of conducting them on their own. The reason for any delay must be scrutinized by a DUI attorney effectively for your case to potentially be dismissed or obtain leverage for a favorable resolution.
2. Consent to Search or Questioning
If you voluntarily agree to stay and answer more questions or allow a search of your car, the officer doesn’t need additional legal justification.
However, it’s important to know:
- You are not required to answer unrelated questions.
- You can decline a request to search your vehicle.
- You can always ask, “Am I free to go?”
If the answer is no, you’re likely being detained, and the officer must justify that continued detention.
3. Use of K-9 Units (Drug Dogs)
Police are allowed to use drug-sniffing dogs during a lawful stop—but only if it doesn’t prolong the stop beyond what’s reasonably necessary.
This rule comes from the U.S. Supreme Court’s decision in Rodriguez, mentioned earlier in this blog. The Court made it clear: once the purpose of the traffic stop is complete, officers cannot extend the detention just to wait for a K-9 unit—unless they’ve developed new reasonable suspicion of a drug-related crime.
In Tennessee, courts follow this same standard. If the dog arrives after the stop should have ended, and there’s no new legal justification for the delay, any evidence the dog finds could be thrown out in court.
Bottom Line
Officers can’t stall or extend a stop just because they hope to find something illegal. Without new reasonable suspicion or your consent, the stop must end when the original purpose is complete.
Detention Outside of Traffic Stops
Not every police stop happens behind the wheel. Sometimes you’re approached on the street, in a parking lot, or even outside your home. In these situations, the same basic legal rules apply—officers can briefly detain you if they have reasonable suspicion of criminal activity.
This type of detention is still considered a Terry stop, and the same constitutional protections apply.
When Can Police Detain You on the Street?
An officer can stop and question you if:
- You match the description of a suspect from a recent crime,
- You’re seen engaging in suspicious behavior (e.g., trying to avoid police, lingering near a closed business late at night),
- There’s a report of illegal activity in the area and you appear connected to it.
But like traffic stops, these street detentions must be brief and focused on confirming or dispelling the officer’s suspicion. If police want to go further—such as searching you or taking you into custody—they need either your consent or probable cause.
Can You Walk Away?
It depends on the nature of the stop.
- If it’s a consensual encounter—meaning you’re free to leave and the officer hasn’t asserted authority—then yes, you can walk away.
- If it’s a Terry stop, you are not free to leave, but the officer still needs reasonable suspicion to justify that detention.
How do you know which it is? You can politely ask:
“Am I being detained, or am I free to go?”
That question forces the officer to clarify the nature of the interaction—and protects your rights if the stop turns into something more serious.
Limits Still Apply
Even during a street detention, officers can’t hold you for an extended time or conduct a search without legal cause. If the stop drags on without new justification, or if you’re moved to another location without consent or probable cause, the encounter may become an illegal arrest.
In Tennessee, courts have thrown out cases where police detained individuals too long without escalating justification. The rule is simple: short, focused, and legally grounded.
When Does a Detention Become an Arrest?
One of the most important distinctions in any police encounter is knowing when a temporary detention turns into a formal arrest—because the legal standards and your rights change dramatically at that point.
During a detention (like a Terry stop), police only need reasonable suspicion to briefly hold you. But to make an arrest, they must have probable cause—a higher legal threshold that requires objective evidence that you’ve committed a crime.
Signs You’ve Been Arrested—Even If No One Says So
You don’t have to hear the words “you’re under arrest” for an arrest to occur. Tennessee courts look at the total circumstances to determine whether a detention has turned into an arrest. Some key signs include:
- You’re handcuffed or physically restrained
- You’re moved to another location (like a police station)
- The stop becomes excessively long without justification
- The officer tells you that you’re not free to leave
- You’re placed in the back of a patrol car without consent
If any of these happen without probable cause, the encounter may be deemed an illegal arrest—and any evidence gathered during that time may be inadmissible in court.
Why It Matters
The distinction between detention and arrest isn’t just technical—it can determine whether:
- Evidence gets thrown out,
- Charges get dismissed,
- Or your constitutional rights were violated.
So, if the police escalate a brief stop into something more intrusive without sufficient cause, that may form the basis for a strong legal defense.
What Happens If Police Hold You Too Long? How Our Attorneys Can Help
If you believe the police detained you longer than the law allows, your rights may have been violated—and that can have a major impact on your case. At Barnes & Fersten, our criminal defense attorneys dig into the details of your stop, including:
- How long it lasted,
- What the officer said and did,
- Whether there was legal justification at each stage, and
- Whether any evidence was obtained illegally.
We use this information to challenge the stop and push to suppress evidence that was gathered as a result of an unlawful detention. In some cases, that can lead to charges being reduced or even dismissed entirely.
Charged After a Police Stop? Contact Barnes & Fersten Today
If you’ve been charged with a crime after a traffic stop or police encounter in Tennessee, don’t assume everything the officer did was legal. Whether it was a DUI stop, drug investigation, or a simple roadside questioning that escalated, your case may hinge on what happened in those first few minutes with the police.
Contact Barnes & Fersten today by calling 865-805-5703 or filling out our contact form to schedule a free consultation. We’ve helped clients across East Tennessee challenge unlawful detentions and get charges reduced or dismissed. The sooner you act, the sooner we can begin building a strong defense for your case.
Attorney At Law, Managing Partner
Brandon D. Fersten is an esteemed Knoxville attorney practicing DUI, criminal defense, and juvenile law. Known for his empathetic approach and commitment to his clients, he brings a record of favorable case outcomes including dismissals and not guilty verdicts at jury trials resulting in Brandon being recognized as one of the “Top 40 Under 40” in Criminal Defense, U.S. News’ Best Lawyers: “Ones to Watch,” and Super Lawyers’ “Rising Stars”. Brandon’s professional accolades, combined with his passion for justice, position him as a reliable criminal defense advocate in the East Tennessee legal landscape, including Knox County, Blount County, Sevier County, Loudon County, Roane County, Anderson County, Cumberland County, Hamblen County, Monroe County, and McMinn County.
