“Remember this,” said the latter earnestly, “that if once the police get hold of a thing or a person it's no use relying on my, or Murble's, or anybody's professional discretion. Everything's raked out into the light of common day, and very common it is. Here's Denver accused of murder, and he refuses in the most categorical way to give me the smallest assistance.”
“Jerry's an ass. He doesn't realize——”
“Do you suppose,” broke in Biggs, “I have not made it my business to make him realize? All he says is, 'They can't hang me; I didn't kill the man, though I think it's a jolly good thing he's dead. It's no business of theirs what I was doing in the garden.' Now I ask you, Wimsey, is that a reasonable attitude for a man in Denver's position to take up?”
Peter muttered something about “Never had any sense.”
“Had anybody told Denver about this other man?”
“Something vague was said about footsteps at the inquest, I believe.”
“That Scotland Yard man is your personal friend, I'm told?”
“So much the better. He can hold his tongue.”
“Look here, Biggs, this is all damned impressive and mysterious, but what are you gettin' at? Why shouldn't I lay hold of the beggar if I can?”
“I'll answer that question by another.” Sir Impey leaned forward a little. “Why is Denver screening him?”
Sir Impey Biggs was accustomed to boast that no witness could perjure himself in his presence undetected. As he put the question, he released the other's eyes from his, and glanced down with finest cunning at Wimsey's long, flexible mouth and nervous hands. When he glanced up again a second later he met the eyes passing, guarded and inscrutable, through all the changes expressive of surprised enlightenment; but by that time it was too late; he had seen a little line at the corner of the mouth fade out, and the fingers relax ever so slightly. The first movement had been one of relief.
“B'Jove!” said Peter, “I never thought of that. What sleuths you lawyers are. If that's so, I'd better be careful, hadn't I? Always was a bit rash. My mother says——”
“You're a clever devil, Wimsey,” said the barrister. “I may be wrong, then. Find your man by all means. There's just one other thing I'd like to ask. Whom are you screening?”
“Look here, Biggs,” said Wimsey, “you're not paid to ask that kind of question here, you know. You can jolly well wait till you get into court. It's your job to make the best of the stuff we serve up to you, not to give us the third degree. Suppose I murdered Cathcart myself——”
“I know I didn't, but if I did I'm not goin' to have you askin' questions and lookin' at me in that tone of voice. However, just to oblige you, I don't mind sayin' plainly that I don't know who did away with the fellow. When I do I'll tell you.”
“Yes, I will, but not till I'm sure. You people can make such a little circumstantial evidence go such a damn long way, you might hang me while I was only in the early stages of suspectin' myself.”
Circumstantial evidence is evidence in which an inference is required to connect it to a conclusion of fact, like a fingerprint at the scene of a crime. By contrast, direct evidence supports the truth of an assertion directly—i.e., without need for any additional evidence or the intervening inference.
On its own, it is the nature of circumstantial evidence for more than one explanation to still be possible. Inference from one piece of circumstantial evidence may not guarantee accuracy. Circumstantial evidence usually accumulates into a collection, so that the pieces then become corroborating evidence. Together, they may more strongly support one particular inference over another. An explanation involving circumstantial evidence becomes more valid as proof of a fact when the alternative explanations have been ruled out.
Circumstantial evidence allows a trier of fact to deduce a fact exists. In criminal law, the inference is made by the trier of facts in order to support the truth of assertion (of guilt or absence of guilt).
Testimony can be direct evidence or it can be circumstantial. If the witness claims they saw the crime take place, this is considered direct evidence. For instance, a witness saying that the defendant stabbed the victim is direct evidence. By contrast, a witness who says that she saw the defendant enter a house, that she heard screaming, and that she saw the defendant leave with a bloody knife gives circumstantial evidence. It is the necessity for inference, and not the obviousness of a conclusion, that determines whether or not evidence is circumstantial.
Forensic evidence supplied by an expert witness is usually circumstantial evidence. A forensic scientist who testifies that ballistics proves the defendant’s firearm killed the victim gives circumstantial evidence from which the defendant’s guilt may be inferred. (Note that an inference of guilt could be incorrect if the person who actually fired the weapon was somebody else.)
On the other hand, the additional circumstantial evidence of the defendant's fingerprint on the trigger would dovetail with this piece to provide corroborating evidence.
The two areas in which circumstantial evidence is of most importance are civil and criminal cases where direct evidence is lacking.
“H'm!” said Biggs. “Meanwhile, I tell you candidly, I am taking the line that they can't make out a case.”
“Not proven, eh? Well, anyhow, Biggs, I swear my brother shan't hang for lack of my evidence.”
"Not proven" is a verdict available to a court in Scotland.
Under Scots law, a criminal trial may end in one of three verdicts: one of conviction ("guilty") and two of acquittal ("not proven" and "not guilty").
Historically, the two verdicts available to Scots juries were that the case had been "proven" or "not proven". However in a dramatic case in 1728 the jury asserted "its ancient right" to bring in a "not guilty" verdict even when the facts of the case were proven (see jury nullification). As the "not guilty" verdict gained wide acceptance amongst Scots juries, Scots began to use "not guilty" in cases where the jury felt the "not proven" verdict did not adequately express the innocence of the defendant. Shrewd defence then further encouraged this interpretation in order to persuade juries unwilling to bring in a "not guilty" verdict that the "not proven" could be brought in as a lesser or "third verdict".
The result is the modern perception that the "not proven" verdict is an acquittal used when the judge or jury does not have enough evidence to convict but is not sufficiently convinced of the defendant's innocence to bring in a "not guilty" verdict. Essentially, the judge or jury is unconvinced that the suspect is innocent, but has insufficient evidence to the contrary. In popular parlance, this verdict is sometimes jokingly referred to as "not guilty and don't do it again".
Out of the country, the "not proven" verdict may be referred to as the Scottish verdict, and in Scotland itself it may be referred to colloquially as the bastard verdict, which was a term coined by Sir Walter Scott, who was sheriff in the court of Selkirk.
"Of course not,” said Biggs, adding inwardly: “but you hope it won't come to that.”
A spurt of rain plashed down the wide chimney and sizzled on the logs.