Why does highway traffic stop

By choosing I Accept , you consent to our use of cookies and other tracking technologies. Why do traffic jams sometimes form for no reason? Share this story Share this on Facebook Share this on Twitter Share All sharing options Share All sharing options for: Why do traffic jams sometimes form for no reason? Reddit Pocket Flipboard Email. Why phantom traffic jams form If there are enough cars on a highway, any minor disruptions to the flow of traffic can cause a self-reinforcing chain reaction: one car brakes slightly, and the ones behind it brake just a bit more to avoid hitting it, with the braking eventually amplifying until it produces a wave of stopped or slowed traffic.

Inevitably, traffic waves formed: So who's to blame for these traffic jams? The solution to phantom traffic jams A prototype of Google's self-driving car. Google In the short term, there are some things engineers can do to cut down on these traffic jams. Next Up In Technology.

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For more newsletters, check out our newsletters page. And that is the possibility for which I always prepare, in order to return safely to my family at the end of my shift.

This seriousness and initial distrust can make an officer come across as curt or unfriendly sometimes. Please know that it isn't personal, it's just playing it safe. What about bicycles? Stopping bicycles is somewhat safer for officers, because we have a better view of what the rider is doing and there are fewer places to hide weapons.

But it is always serious. Criminals ride bikes, too. And weapons can be concealed in clothing. When I stop someone who is riding a bike, I usually ask them to dismount and sit on the curb. It's usually more comfortable for the rider and it gives me a warning if they decide to get up and run or fight. How should I behave?

The best approach when being stopped is to be human and considerate and responsible. Turn off the radio. And remember that your officer has heard every excuse for violating the law-if you were speeding, an honest apology and willingness to take responsibility can be refreshing. It might even earn a warning. What if I disagree with the ticket? Of course officers make mistakes on occasion-they're human beings.

Or there might have been extenuating circumstances. But if you disagree about the violation, arguing the ticket on the spot in traffic can be dangerous for everyone-save it for court. That is exactly what a judge and the judicial system are for. Don't officers have better things to do? The Portland Police Bureau has many units that are tasked with investigating various crimes. We have homicide detectives, a child abuse unit, a sex crimes unit, a drugs and vice unit, etc.

The Traffic Division's primary job is to investigate major traffic crimes and crashes, and to enforce traffic laws.

Conducting traffic stops, often at problem locations called in by neighborhood residents, is what they do. In addition, officers assigned to the Patrol function who answer calls , will often do traffic stops between calls to assist the Traffic Division in responding to one of the most common complaints of Portlanders-traffic issues. So the answer is no, they don't have better things to do--if you are stopped by an officer it means they are proactively doing their job and not simply driving around waiting for something to happen.

Table of Contents. Sometimes, police officers driving in obvious police cars with blue and white lights attached to the roof of the car are the ones who do the traffic stops.

However, more and more police departments an unmarked police car to pull over unsuspecting drivers. However, certain demographics are more likely to be pulled over than others, and the consequences for drivers who are subject to a traffic stop vary significantly. According to the Department of Justice, there are 19 million traffic stops per year. The data shows that African Americans are more likely than other racial groups to be pulled over, with 9.

This Department of Justice is part of our traffic stop data collection that was used for our rankings in this article. In addition, we use this data to analyze how often different demographics are pulled over and how these statistics might be cross-examined with racial profiling statistics, though those are not the explicit subject of our article. The data also shows that women are less likely than men to be pulled over. In addition, year-old young drivers are the most likely age group to have a police-initiated traffic stop, with the likelihood steadily decreasing with age.

Since drivers under the age of 25 are less experienced behind the wheel, they often also pay higher insurance rates. Not all drivers who are pulled over believe that their stop was justified.

In fact, only Not surprisingly, drivers are more likely to perceive the stop as legitimate when police officers provide a reason for the stop Among all traffic stops, police officers provided a reason for the stop in Blacks are the largest racial group to be pulled over, which contributes to the financial burden of driving while black in , which includes higher insurance premiums and reduced mobility.

Department of Justice data shows that police are more likely to give women a reason than men, and police are less likely to give Hispanics a reason than other racial groups, which puts the onus on Hispanic drivers to know their legal and auto insurance rights.

Additionally, both black drivers and Hispanic drivers are significantly less likely to believe they were pulled over justly even when the police officer provides a reason. The outcomes of traffic stops vary by demographics as well. Among all traffic stops, only Instead, It is well known that traffic violations increase auto insurance rates. While black drivers and white drivers have similar results from traffic stops, Hispanics are more likely than other races to get a ticket and less likely to get a warning.

Hispanics are also the least likely racial group to have no enforcement action taken. Since auto insurance rates are partially based on driving records, consequences such as getting a ticket or an arrest could also lead to higher premiums, raising the financial burden of driving for certain demographic groups.

In recent years, a growing body of research has investigated the effectiveness of body cameras in police-initiated contact, such as traffic stops. In , only 47 percent of law enforcement agencies used body-worn cameras BWCs , accounting for , BWCs nationwide. Among law enforcement agencies that use BWCs, more than 90 percent require their officers to turn the cameras on during traffic stops.

While there is currently no federal law governing the use of body cameras in police-community encounters like traffic stops, several state and local governments have passed legislation regarding their use in an effort to improve police and civilian safety, professionalism, and fairness.

Although some of these may have had an effect, many police departments still employ tactics that target minorities and often lead to a disproportionate amount of discrimination and police on civilian violence. One of the worst cities for this is Los Angeles, which ranks as our number one city with the greatest potential for reducing its police department budget. It also ranks as the worst city for police department spending per capita out of the 20 most populous cities and largest city police budgets.

Now, back to the reasons police officers pull over drivers. The number of reasons officers will pull over drivers is likely incredibly large and relates to all sorts of situations like nighttime driving or speeding through a construction zone.

Officers are especially vigilant during rush hour, as some cities have more rush hour fatal crashes than others especially if they are the worst cities for rush hour fatal crashes. What are the top 10 reasons police officers pull over drivers? Scroll down to find out. Scroll down to see what we found. Increasing the spacing of vehicles dampens the effect of slowdowns by cars in front of a given car, so that the slowing is not amplified until it becomes a phantom jam, the researchers said.

A video from the project shows a train of autonomous robots running along a track without bilateral control; they eventually back up in phantom jams. But when the robots are switched over to bilateral control by flashing the lights in the room , each autonomous robot tries to keep itself halfway between the robot in front and the one behind; the phantom jams disappear as a result, Horn said. Since starting his research on phantom traffic jams, Horn has learned that schools of fish and flocks of birds and bats use similar spacing strategies to avoid hitting each other while swimming or flying in densely packed groups.

In particular, studies of millions of bats emerging at dusk from caves in Southeast Asia showed that each bat used a form of bilateral control to reduce the likelihood of collisions with other bats in the densely packed swarm, Horn said. Unlike bats, birds and fish, however, humans have difficulty judging distances behind them. To address that weakness, Horn is now working with the car company Toyota to enable a form of bilateral control via modifications to existing adaptive cruise control systems, which use forward-facing sensors to judge the distance to the vehicle ahead.