The anti-racial demonstrations sparked by the "Black Floyd" incident have been going on around the world for more than three months, during which time the conflict between the American people and the American police has reached its highest level ever. In the face of chaotic demonstrations and even riots, the US government dispatched a large number of police to maintain social order.
At the same time, in order to avoid being arrested and imprisoned, the American people are racking their brains to grasp the movements of the police in order to avoid them. Twitter users, for example, @NYPDScanner1 opened social accounts that specifically released various police voices during protests. Various apps that can listen to police radio channels in various cities in real time are also very popular in the United States. One app called Police Scanner saw downloads skyrocket by 125 percent within a week of the mass march.
In fact, in the United States, the content of the police's use of radio conversations is completely public, and people can enter the police channel for "eavesdropping" by using the police radio scanner. A police radio scanner is a device used to scan radio frequencies used by law enforcement. The scanner is capable of listening to multiple frequencies at once and playing back the transmission when those frequencies are received.
The appearance of the earliest scanners was the traditional radio model, and after nearly 100 years of development, the emergence of social networks and smartphones, the "police radio scanner" has slowly changed from an object name to an app or an account.
So, how was the police radio scanner invented? What problems does its birth map out of the context of different eras in the United States? In this issue of "Science and Technology Collection", the detective will have a good chat with you about the "history of the American people eavesdropping on the police".
< h1 class="pgc-h-arrow-right" > the emergence of police channels</h1>
To understand the history of wiretapping police, it is necessary to understand the history of the use of radio frequencies by police to communicate.
In the 1920s, police agencies have been using radio for communication and communication. But the walkie-talkie hadn't even been invented yet, and even the portable radio hadn't been invented. As a result, the police can only broadcast publicly through public commercial radio channels, while americans only need to sit around in front of the radio like a shoe cabinet to listen to the police channels openly.
Early home radios were all very bulky, and the pictures came from the network
In fact, at this stage, the police channel is only used to broadcast some security precautions and wanted warrants, etc., the police do not put too much confidential information on the radio station for broadcasting, and even the audience will call the radio station to ask for songs. For the audience, the police radio at that time was not much different from ordinary news broadcasts and entertainment broadcasts, so the information and information at their fingertips naturally did not arouse the curiosity of the American people too strongly.
In 1936, the predecessor of Motorola Corporation: a radio communication company called "Made by Calvin", came out of nowhere, and introduced a wireless radio for police cars that could receive one-way broadcasts, so that the alarm information could be transmitted one-way to the police who were on duty through the radio, so as to make a rapid response to key information.
Member of the New York Metropolitan Police in 1930, using radio to communicate with police radio cars; image from Bloomberg
New York City, which has a very high crime rate, was the first to apply this method to police enforcement. According to crime scene photojournalist Weegee, although police radios were still public at the time, because the price of wireless car radios at that time was as high as $735, very few people were able to "track" police movements based on information on police stations. It can be said that at that time, the only people who could rush to the crime scene at that time were the policemen who drove police cars equipped with wireless radios, and only the rich people in the city.
At that time, the activities of the police were only the exclusive activities of the rich. Thrill-seeking high-class people in New York City tend to drive aimlessly around the city, and as soon as they learn from the radio where the crime has occurred, they will immediately go to the scene of the crime to experience the excitement of visiting the crime scene. "If they had witnessed a murder at the time, these people would have bragged about it in their social circles for weeks or even months." Vigie said in a later autobiography.
It is obviously not a good thing to have ordinary people directly at the scene of the crime, especially in some violent crime scenes such as kidnapping, robbery, etc. Too many idle people will make the police unable to control the scene well, and these lively "high society" will often provoke these violent criminals with their words in order to be able to witness the violent crimes they dream of, resulting in the loss of hostages and innocent people. And the multiple deaths of the hostages have also made the police blamed by society, although it is not their fault.
"Shortwave Process" promotes the benefits of homemade shortwave scanners, and the picture comes from the network
In order not to let such things happen frequently, the New York Police Department (NYPD) decided to encrypt police channels. Although this encryption method only shortens the long radio wave to the short one, the success rate of NYPD in dealing with violent crimes has indeed increased a lot when the "encryption policy" was first piloted.
However, this method of encryption has aroused people's curiosity. Some ordinary people began to make their own shortwave receivers, and even at that time, some people published an article in magazines called "Shortwave Craft" detailing how to diy shortwave receivers at home to monitor police radios. The author declared: "This is not a voyeur's toy, but a weapon to better serve the public society." This was also the prototype of the later police radio scanner.
Police radio scanner full of "free breath"
It wasn't until the 1970s that the outbreak of the first oil crisis and the long Cold War with the Soviet Union ushered American society into an era of chaos and change. A large number of new ideas and beliefs rose in that era, and when the change of thought reached its peak, it was bound to lead to the heating up of social contradictions and thus into social conflicts.
At that time, there were many demonstrations in American society, including anti-war, new Christianity and new feminist movements. The demonstrators of these movements began to gather frequently in the streets of major cities, and the police who maintained social order naturally became the "enemies" of these demonstrators. In anti-Vietnam War marches in Chicago and Ohio, police shot demonstrators.
Anti-Vietnam War march, image from the Internet
In order to protect themselves, these demonstrators began to "listen" to the police radio on a large scale. It was in this social context that the first commercialized police radio scanner began to enter the market. It can be said that it entered the commercial market with a certain "free atmosphere".
According to police recollections at the time, when these scanners began to be widely used, people began to know the movements of the police station. They know exactly where the police go, what they do, whether they are armed or not, and some drug dealers even use these scanners to obtain the location of the police officer and kill him in retaliation for the police's crackdown on them.
In order to deal with this situation, the Us police have adopted a series of methods. For example, in the 1980s, the U.S. police department uniformly used the 800MHz band far beyond the frequencies of civilian radios and used fixed code as a "secret code" in ordinary dialogue to communicate. In Denver, police stations remain silent for a long time, and some city police stations exclude classified departments such as the FBI and the Drug Enforcement Administration from radio stations.
The U.S. government is also legally constraining the once-"flooded" mobile scanners. Under New York State law, any use of a vehicle-mounted police scanner carries up to 6 months in prison unless you hold an FCC's amateur radio operator license. In the future, some cities have followed suit and introduced relevant laws.
The introduction of this decree is very good at limiting the use of police scanners to the home or indoors that cannot be moved, unless you are a superhero like "Spider-Man", you will never arrive or escape the crime scene before the police. A series of measures have led to a massive loss of police radio scanning enthusiasts in the United States.
Although the way the wavelength + code is changed is really good from the 80s onwards to protect the mission confidentiality of some special law enforcement and service departments. But since the beginning of the 21st century, many law enforcement agencies in the United States have begun to consider making radio public again.
Because some local law enforcement agencies believe that encryption policies will bring great difficulties to daily work. Paul Holaday, fire chief of Orange County, Los Angeles, said in an interview with The Los Angeles Times: "We are considering removing the radio encryption policy because the three departments of police, medical and fire use different channels and codes, which will lead to different systems not working well together in some emergencies." ”
Every police officer in the modern era wears a single-person radio, and the picture comes from the network
Lindsay Blanton, founder of Commercial Police Radio Scanner Company Broadcastify, also said in an interview with the media: "At present, police stations in many cities, including NYPD, tend to make police stations public, because this not only reduces the cost of communication between the stations but also allows some people in emergencies to quickly find the police through the radio for help." ”
At present, because of the "Floyd Incident", the american people and the police are once again on the opposite side. With the emergence of some listening apps, people have begun to use the "eavesdropping" method to supervise and even attack the behavior of the police.
In fact, the emergence of commodities such as police radio scanners and phenomena such as "listening police" itself has a strong background of the times, and its use will change with the changes in the background of the times. For example, in the "Boston terrorist attack" in 2013, the police broadcast the latest search information on a 24-hour loop through the radio, so that the residents in the community could feel enough to feel safe. And when the background of the times puts the police and the people on the opposite side, the fully open radio is a weapon for both sides to attack each other.
The scene of the Boston terrorist attack, picture from the Internet
Therefore, the "surveillance of the police" is a double-edged sword. As the most famous quote in the tech world goes, "Technology only depends on who uses it." "When high-tech is used by responsible and responsible governments, it must benefit the people and promote the cooperation between the police and the people and the stability of society."