Limit of detection

“ Because it can detect what is said anywhere-not just on the telephone-bugging presents especially serious threats to privacy.
Detection of surveillance devices is difficult, particularly where an installation is accomplished by a skilled agent. Isolated instances where equipment is discovered in operation therefore do not adequately reflect the volume of such activity; the effectiveness of electronic surveillance depends in part upon investigators who do not discuss their activities. ”

“ The two systems, those of the London and Parisian detective, differ most essentially. With us, it is as if the general commanding an army in the field was to send spies into the enemy’s camp, taking care they were dressed and behaved themselves in such a manner that every one would know who they were. On the other hand, the French system of detection is based on the principle that the enemy—namely, the criminals amongst whom they have to make their inquiries—should never be able to discover who the spies are. ”

“ I will begin what I have to say by remarking that the tracing out of a crime like this differs in nothing, except as regards the subject-matter, from the search for a scientific truth. The forcing of man's secrets is like the forcing of nature's secrets. Both are pieces of detective work. The methods employed in the detection of crime are, or rather should be, like the methods employed in the process of discovering scientific truth. In a crime of this sort, two kinds of evidence need to be secured. ”

“ I never believe in trying to bluff a full hand. Had I had but ordinary detectives with whom to deal, I make bold to say I should have come off rich and triumphant. I had no means of knowing that I was to play with a chemist who would use against me the latest scientific implements of criminal warfare. It is, therefore, to the extraordinary means used for my detection that I impute my defeat, rather than to any bungling of my own. ”

“ But is it not rather improbable that those who have so far transgressed as to apprehend the vigilance of the police, should venture into the very places where they must be aware of immediate detection? ”

“ Every profession is marred by its little jealousies, and why should the coterie of detection be exempt? I hope I may never follow an example so deleterious, and thus be tempted to express my contempt for the stupidity with which, as all persons know, the official detective system of England is imbued. ”

“ Some of these processes are well understood and some little understood by man. As is the case with electrical and other forms of scientific research the field of scientific criminal detection hardly has been scratched. Research is constant and no doubt will be perpetual. No one knows where any sort of research will lead. Scientific detectives call attention to this fact:
"Such research is valuable not only in the matter of law enforcement but might prove of inestimable value in other fields. ”

“ This feeling was not unnatural, since the detection came through a discredited channel, the spotter. Rare are the circumstances where secret service should be necessary. There is something inherently wrong in any system which has to gain routine information by indirect methods. ”

“ There is so much elaborate hocus-pocus around the whole matter of criminal detection that it makes a detective wonder why people think he acts that way. The fiction writers want to call it a science, and attach blood-pressure instruments to people’s arms, and give them Freud tests—they forget that your innocent man is always nervous, and acts more like a guilty one than the criminal himself, even his insides. They forget that these machines are operated by the most catankerous one of all, the human machine. ”

“ To inherit his broad land;
And you come here but to question
If detection is at hand.
Do you dream to cheat a wizard,
As you cheated that poor lad?
Yes, detection dogs your footsteps,
You shall see the murdered lad. ”

“ Hardly a serious crime is investigated without the application of one or [Pg 223] other of these scientific methods of detection, and with each success the career of the criminal becomes increasingly difficult and arduous, and his chances of success more remote. Of remarkable discoveries of crime the microscope, the camera, and the spectroscope furnish the most subtle instances, and it is quite possible that before long other methods of investigation, founded on the most recent scientific achievements, will also be brought into operation. ”

“ The most valuable methods of detecting forgery have been based upon the use of the microscope, which will frequently reveal alterations that are quite invisible to the naked eye.
For instance, a letter may have been so carefully erased as to defy detection by ordinary examination, but a microscopical examination will show the slightly roughened surface of the paper, where the fibres have been disturbed in the process of erasure. ”

“ Men who have been suspected for years, but have managed to evade detection, have been pounced upon by detectives at most unexpected moments; but the temptation is so strong that, despite the penalty, the practice still goes on, but to a smaller extent than before. ”

“ The science of detection——"
Father Brown snapped his fingers with the same animated annoyance. "That's it," he cried; "that's just where we part company. Science is a grand thing when you can get it; in its real sense one of the grandest words in the world. But what do these men mean, nine times out often, when they use it nowadays? When they say detection is a science? When they say criminology is a science? They mean getting outside a man and studying him as if he were a gigantic insect: in what they would call a dry impartial light, in what I should call a dead and dehumanized light. ”

“ Crawshay went on reflectively, "how the science of detection has changed during the last ten years. When I was an apprentice at it—and though you may not think it. Miss Sharey, I am a professional, not an amateur, although I am generally employed on Government business—secrecy was our watchword. We hid in corners, we were stealthy, we always posed as being something we weren't. We should have denied emphatically having the slightest interest in the person under surveillance. In these days, however, everything is changed. ”

“ We cannot blind ourselves to what experience unmistakably teaches: that even apart from the express threat, the basic techniques present here-the secret and incommunicado detention and interrogation-are devices adapted and used to extort confessions from suspects. Of course, detection and solution of crime is, at best, a difficult and arduous task requiring determination and persistence on the part of all responsible officers charged with the duty of law enforcement. ”

“ More people come into the plot; the increased activity drives the culprits to shifts, and these shifts are perilous from the very circumstance of being forced. We thus find detection often more easy and certain in populous towns, with a good staff of criminal officers, than in quieter places, where both plotters and shifts are proportionally fewer. ”

“ Detection depends largely, of course, upon the knowledge, astuteness, ingenuity, and logical powers of police officers, although they find many independent and often unexpected aids, as we shall see. The best method of procedure is clearly laid down in police manuals: an immediate systematic investigation on the theatre of a crime, the minute examination of premises, the careful search for tracks and traces, for any article left behind, however insignificant, such as the merest fragment of clothing, a scrap of paper, a harmless tool, a hat, half a button ”

“ Everybody knows that the universe contains enough spies or enough spectres to kill the most healthy and vigorous vicar. The drama of detection is in discovering how he can be killed decently and economically, within the classic unities of time and place. ”

“ The recent advances in the methods of telegraphing a facsimile of a specimen of handwriting or a sketch, or of reproducing a photograph at a distance have greatly increased the difficulties of criminals escaping detection, and the telectrograph, as it is termed, will prove a powerful weapon in the hands of the detective. ”

“ It is to be hoped that during these operations, members will abstain from making inquiries or discussing the subject in any manner, for we cannot say when we undertake to answer members, but that at the same time we are answering the inquiries of our enemy, furnishing important information, and giving important clues to detect and suppress our work. The mystery of an unknown power striking in the dark, always able to avoid [247] detection, is far more terrible than the damage inflicted. ”

“ Miss Cornelia resented his off-hand demolition of the mental card-castle she had erected with such pride.
"I have read a great deal on the detection of crime," she said hotly, "and——"
"Well, we all have our little hobbies," he said tolerantly. "A good many people rather fancy themselves as detectives and run around looking for clues under the impression that a clue is a big and vital factor that sticks up like—well, like a sore thumb. ”

“ The detective smiled, and said, “You have no idea, my lord, of the difficulties of detection. They are almost incalculable. I am sure we all of us do our best. If we don’t succeed, it is some unknown cause which lies far beyond our reach. Every effort has already been made on the part of the local constabulary as well as the metropolitan. ”

“ It is to be doubted whether the law can reach such cases, because detection would always involve an intrusion into the living apartments of families, and would make in time such hostility that the law itself would have to be repealed. ”

“ Because the SART signal is stronger than any surrounding radar returns, it will be easily sensed by any nearby radar. But because it is much weaker than the radar, its own range is the limiting factor in detection. ”

“ The answer, from a technological planet, was a technological one. Build a space fleet and equip it with some sort of a detection-fire network.
This was done in record time. The Attison Detector was developed, a cross between radar and the electroencephalograph. Any alteration from the typical human brain wave pattern of the occupants of a Detector-equipped ship would boost the indicator around the dial. Even a bad dream or a case of indigestion would jar it.
It seemed probable that any attempt to take over a human mind would disturb something. ”

“ A divided responsibility simply doubles the criminal's opportunities for escape.
Among the many difficulties of the detective's work, none are more embarrassing than the early development of false clues. In the stories heretofore published, the direct steps leading to the detection and arrest of the criminals have been related, without referring to the innumerable other investigations, which were progressing simultaneously, and which, though involving the expenditure of much thought, time, and money, proved after all to be of no value whatever in developing any evidence in the case. ”

“ Modern community living requires modern scientific methods of crime detection lest the public go unprotected. The increasing slaughter on our highways, most of which should be avoidable, now reaches the astounding figures only heard of on the battlefield. ”

“ His only hope of escaping detection was his knowledge that the negative-detector, developed in the Orionad for use against sub-ships was less sensitive as to range than the positive-detector. The establishment of negative evidence is never conclusive. And his souped-up detector would outrange any but another souped-up job.
So Guy coasted for days, which at five thousand miles took him far, far beyond the orbit of Pluto. ”

“ I need hardly say how very much is due to decision in the business of detection. A single minute will often peril the object of your inquiry, and then it does not often happen—​at least I have not found it—​that the patience that is required in ferreting is joined to the power of dashing at an emergency.”
“You can’t expect an impetuous man to be patient,” observed Peace. “All are not constituted alike, but it requires a man of exceptional qualities to hunt down thieves or robbers, and, as you say, inflexibility of purpose or decision is absolutely requisite.” ”

“ For me to set foot in any one of the three would be to run the risk of almost certain detection, and in my case detection would mean hopeless incarceration for the poor remainder of my days. To the world at large I may seem nothing but a simple country gentleman, living a dull life in a spot remote from all stirring interests. ”

“ "There are no crimes and no criminals in these days," he said, querulously. "What is the use of having brains in our profession. I know well that I have it in me to make my name famous. No man lives or has ever lived who has brought the same amount of study and of natural talent to the detection of crime which I have done. And what is the result? There is no crime to detect, or, at most, some bungling villany with a motive so transparent that even a Scotland Yard official can see through it." ”

“ The site is near the target area so that information may be collected through close-in observation and sound detection. The remainder of the team stays in the hide site. The surveillance site and the route to and from it are selected during good visibility. Members go in and out of the surveillance site during limited visibility. One member observes, one records, and one maintains security to the rear and flanks. Only passive night vision devices are used to help prevent detection. ”

“ These latter may be—indeed, they generally are—well meaning people, anxious to serve the cause of justice; though, on the other hand, they are sometimes spiteful meddlers, striving to fix suspicion upon some personal enemy.
The plan of detection which alone can insure success, must be one which neither forgets nor neglects anything. In investigating any alleged crime, the first questions to be considered are: 1. Has any crime been perpetrated, and, if so, what? ”