In The Damnation of John Donellan, reviewed in the last blog post, Elizabeth Cooke refers to Phillips’ views on Sir Justice Buller’s conduct of the Donellan trial. Here, with minor edits, is that section of his book, taken from the Introduction of Famous Cases of Circumstantial Evidence: With an Introduction on the Theory of Presumptive Proof. There are several editions of the book available online; this is from the second edition, published in Boston in 1874 by Estes and Lauriat, accessed via https://bulk.resource.org/courts.gov/b/texts/P1ovAAAAIAAJ.pdf
One expects that Sherlock Holmes had a copy on his bookshelf.
A presumption, which necessarily arises from circumstances, is very often more convincing, and more satisfactory, than any other kind of evidence; it is not within the reach and compass of human abilities to invent a train of circumstances, which shall be so connected together as to amount to a proof of guilt, without affording opportunities of contradicting a great part, if not all, of these circumstances. (Charge of Mr. Justice Bullen [sic], on the trial of Captain Donellan.)
I deny the position. I maintain, that the theory is repugnant to the received principles of jurisprudence; as known to the best foreign writers on the law of evidence. I maintain, that it is not warranted by experience,–the greatest proof of every rule, the proof of proofs. And I may further assert, that it is new to the practice of English law.
[Here, Phillipps goes on to quote from Mascardus and Menochius, and discusses his thoughts on the matter. He takes up the Donellan case again on page xvii of this edition.]
The next occasion on which this doctrine appears, is on the celebrated trial of Captain Donellan, in 1781, before Mr. Justice Buller, in the passage already quoted. But he was altered the position a little, by shifting the criterion from facts to circumstances. Facts, before, were the standard of truth; circumstances are now made to be so. For circumstances cannot lie. But what else are circumstances but facts, or minor facts; and I must take the liberty to say, that circumstances are still more liable to deceive, or to lead to deception, than even facts. A fact being more an object of sight, is easier apprehended by the senses than a circumstances; which, from its triviality, often escapes the attention altogether, is misapprehended, or assigned to a wrong cause.
The trial in question, will afford a most unparalleled illustration of the truth of this observation; it will show the fallibility of circumstances, and the very opposite conclusions which different men will draw from the same appearances.

The Death of Theodosius Boughton
I shall here give the general shape of the case–
If shape it might be called, which shape had none,
Or substance might be called, which shadow seemed.
Sir Theodosius Boughton, a young man of a delicate constitution, had sent to a country apothecary’s shop for a draught of medicine. Different vials appear to have been in his chamber, at the time he took he draught; which was intended to be a composition of rhubarb, jalopy, and lavender water.
He was suddenly seized with convulsions in his stomach, and foaming at the mouth; and expired before he could give any explanation. On rinsing one of the vials, the sediment gave the effluvia of laurel water, which is known to be a strong poison. Convulsions, foaming at the mouth, and sudden death, are the natural effects of that liquid.
But every man who dies in that way, is not, therefore, poisoned. The apoplexy will produce the same effects and appearances: of which disease, the father of the young man was known to have died. No evidence whatever was produced as to the existence of the laurel water.
Captain Donnellan [sic], the brother-in-law of Sir Theodosius, was living in his house at the time of the accident. He was the next heir to the estate, and accordingly, the person who had the most immediate interest in his death. He certainly betrayed some uneasiness on the event, and appearances indicated that he was afraid of being suspected as the author of the mischief. But, if it was natural that he should be suspected, if the cui bono points out the actor of a nefarious deed, it was not unnatural that he should find himself placed in circumstances of peculiar delicacy, and manifest embarrassment and confusion in his conduct.
Captain Donnellan was brought to trial, on a charge of poisoning Sir Theodosius Boughton.
The leading point in every case of this sort, is–did the deceased die of poison? For, if he did not, there is an end of the whole. Where there was no poison, there was no poisoner.
But this was altogether a question to be decided by the opinion of medical men. From what then did they form their opinion? From any of those broad marks, respecting which all men judge alike. No; there was nothing of the kind to guide their judgment. The whole cause turned on circumstances; and conjectures supposed from circumstances never proved. Four physicians inspected the body, on dissection, the eleventh day after the death. They gave their opinion to the jury, and described the circumstances on which that opinion was founded; the four said, they believed him to have died of poison.
The circumstances on which they had given their opinion, were stated, at the trial, to Doctor John Hunter, the most eminent physician of the age. He declared he could not discover, in any of those circumstances, nor in all of them united, any sign of the deceased, having died from poison, nor any symptoms beyond those incident to a man dying suddenly.
Q. from the court to Mr. Hunter. Then, in your judgment, upon the appearance the gentlemen have described, no inference can be drawn from thence that Sir Theodosius Boughton died of poison?–A. Certainly not: it does not give the least suspicion
In questions of science, and above all, in those of medical science, the faith to be reposed in any opinion, will be regulated by the professional eminence of the person giving it. One man’s sight being generally as good as that of another, as to a mere matter of fact; as whether he saw, or did not see such a thing, the learned and the ignorant are upon a par, and one witness to a face is just as good as another. But the case is very different as to a matter of science; for one man’s judgment will outweigh that of many. Upon a point of law or equity, we would not put the opinion of a country attorney, or of four country attorneys, against that of a chief justice, Doctor John Hunter stood, at that time, at the very head of his profession; his opinion face the law to that profession, both in England, and in every country in Europe. Had the profession been to estimate his opinion, and not the jury, a very different verdict would have been given. The case referred peculiarly to to [sic] Doctor Hunter’s line of study,–that of dissection, and the appearances incident to a body on sudden and convulsive death. He pronounced, that the dissection had been irregularly made, and in a way not to afford the true criterion to judge by. And, where the process is irregular, when the experiment is defective, the conclusion must always be vague and doubtful.

John Hunter, Surgeon
The gentlemen composing the jury did not perhaps know the eminence of Mr. Hunter’s character; nor, consequently, the weight due to his opinion. But the judge, on the bench, no doubt knew this; and in balancing the evidence, and in summing up, it was clearly his duty to have stated the great weight to be attached to Mr. Hunter’s observations. He stated nothing of all this; but took them numerically, “four medical men to one.”
Thus, from an irregular dissection, a positive conclusion was admitted.
It is a rule of law, and above all in cases of life and death, that the want of any one circumstance will prevent the effect of the whole. Thus, if the dissection were irregular, the opinion formed in reference to that dissection was a mere nothing. As well may you suppose that proposition itself to be true, which you wish to prove, as that other, whereby you hope to prove it.
Post hoc, ergo propter hoc–a species of argument which often leads to fallacy.
Because the fact immediately followed; therefore it was occasioned by that which it followed. He died immediately after taking the medicine; therefore, he was killed by the medicine.
The present question is, was the process on the trial according to law? Was the conclusion arrived at by regular and legal forms? The grounds on which the legal inference is to be drawn, must always of themselves be clear and certain; there is no presumption upon a presumption; there is no inference from a fact not known.
When the judgment of the law is passed in reference to a certain thing, the existence of that thing should be first clearly made to appear.
The fact of poisoning ought to have been established beyond a shadow of doubt, before any person was convicted as the poisoner.
But the jury, it will be said, were satisfied on this point. Had the evidence been duly summed up by the judge; had they been told, as they ought to have been, that in experimental philosophy, such as the tracing the effects of a particular poison, in tracing the causes, so many and so complicated that lead to death, if the experiment is defective,if the process is vitiated in one instance, the result is also vitiated and defective. Every practitioner in philosophy is sensible and aware of this truth; and wherever he finds that he has erred in his experiment, he sets the case aside, as affording no satisfactory result, and renews his process in another subject.
But, unfortunately, it is a matter of pride, in some men, to be always certain in their opinion, and to appear beyond the influence of doubt. Very different was the practice of that modest and eminent man who gave his evidence on this trial: he was accustomed to the fallaciousness of appearances,–to the danger of hasty inferences from imperfect proofs, and refused to give his assent to an opinion, without facts being first produced to support it. “If I knew,” said Mr. Hunter, “that the draught was poison, I should say, most probably, that the symptoms arose from that; but when I don’t know that that draught was poison, when I consider that a number of other things might occasion his death, I cannot answer positively to it.”
During the whole course of this celebrated trial, there was not a single fact established by evidence, except the death, and convulsive appearances at the moment. These appearances, Mr. Hunter declared, offered no suspicion whatever of poison, and were generally incident to sudden death, in what might be called a state of health; not only there was no fact proved, but there was not one single circumstance proved. One circumstance was supposed from another, equally suppositious, and from two fictions united a third was produced. The existence of the laurel water was thus made out: the sediment found in the vial, from which the unfortunate young man had drunk, was supposed to smell like bitter almonds; for, as the smell of laurel water was not then known to Lady Boughton, she could not trace the resemblance further; bitter almonds were supposed to smell like laurel water.
It is here to be observed, that the smell attached to the vial was momentary, for it was washed out almost immediately, and could not be twice experienced. But what so uncertain as the sense of smell? Of all the human senses, it is the most uncertain, the most variable, and fallacious. It is often different to different men, and different in the same person, at one hour, from what it is at the next; a cold, a slight indisposition, the state of the stomach, a sudden exposure to the air, will extenuate or destroy this impression.
But this train of proof was altogether at variance with principles. In law, as already observed, the arguments should be drawn from one reality to another; but here, the argument turned upon the breath, the smell of a woman, distracted at the moment, with the loss of her son, and ready to ascribe that evil to the first thing that came in her way.

The Donellan trial, 1781
All proof must being at a fixed point. The law never admits of an inference from an inference. Two imperfect things cannot make one perfect. That which is weak, may be made stronger; but that which has no substance, cannot be corroborated. The question is never what a thing is like; but the witness must swear to his belief, as to what it is. A simile is no argument. Upon the principle, that comparison of hands is no evidence, in a criminal trial, comparison of smells must be held to be equally defective. Besides, there are a variety of articles that resemble bitter almonds in the smell, and many of these altogether innoxious.
In circumstantial evidence, the circumstance and the presumption are too often confounded; as they seem to have been throughout this trial. The circumstance is always a fact; the presumption is the inference drawn from that fact. It is hence called presumptive proof; because it proceeds merely on presumption or opinion. But the circumstance itself is never to be presumed, but must be substantively proved. An argument ought to consist in something that is itself admitted; for who can prove one doubtful thing by another. If it was not laurel water, that Sir Theodosius drank, the proof fails as to the effect; and certainly, some of the usual proofs, some of the common indicia or marks of things, should have been established. Where did the prisoner procure it? From whom did he obtain it? Where, and what time–and by whom, or how did he administer it? [A/N: Footnote containing quote from Quintillan here omitted] Nothing of this kind was proved.
The whole proof, as to laurel water, rested upon the comparison of the smell. Question to Doctor Parsons, “You ground your opinion upon the description of its smell by Lady Boughton?” Answer: “Yes, we can ground our opinion upon nothing else but that, and the subsequent effects.”
But the judgment of the cause from its effects, Mr. Hunter has already shown to be equally conjectural as that formed from its resemblance in smell.
The proof proceeds. He was supposed to be poisoned, because it was believed to be laurel water; and it was believed to be laurel water, because he was supposed to be poisoned. We will not say that both of these suppositions might not have been true; yet still they were but conjectures, unsupported by any proof, and formed against all the rules of law.
But the accused, it is said, furnished the proof against himself, by his own distrust of his innocence. He no doubt betrayed great apprehensions of being charged with murder; but are innocent men never afraid of being thought guilty?
We readily recognize all the general truisms, and commonplace observations, as to the confidence of innocence, and the consciousness of guilt; but, we find, from history, that innocence loses its confidence, when oppressed with prejudiced; and that men have been convicted of crimes, which they never committed, from the very means which they have taken to clear themselves.
“An uncle who had the bringing up of his niece, to whom he was heir at law, correcting her for some offense, she was heard to say, ‘Good uncle, do not kill me;’ after which time she could not be found; whereupon the uncle was committed upon suspicion of murder, and admonished, by the next assizes; against which time he could not find her, but brought another child, as like her in years and person as he could find, and apparelled her like the true child; but on examination she was found not to be the true child. Upon these presumptions (which were considered to be as strong as facts that appear in the broad face of day), he was found guilty and executed; but the truth was, the child, being beaten, ran away, and was received by a stranger; and afterwards, when she came of age to have her land, came and demanded it, and was directly proved to be the true child.
The above case was referred to by Lord Mansfield, in his speech in the Douglass cause, as an illustration that forgery, and falsehood itself, has been sometimes used to defend even an innocent cause. “It was no uncommon thing,” he observed, “for a man to defend a good cause by foul means, or false pretenses.”
Captain Donellan was liable to suspicion, and to great suspicion, on the general relations of the subject, independent of particular circumstances, and would have been suspected by all the world, had he been never so innocent.
In the first place, it was a well-known fact, that he had been obliged either to quit the army (to which he originally belonged), or had been cashiered by the sentence of a court-martial.
Secondly, he was of all other men the person who was to have gained by the death of Sir Theodosius Boughton; to whose estate and property he succeeded as his brother-in-law. No other human being had an interest in the case. [A/N: This is not true; however, without real detective work, it is unlikely that the other suspects would have been readily uncovered.] Such is the disposition in human nature (founded perhaps on a too just knowledge of our feelings and principles of action), that first suspicion always points to the person who is to gain by it, as the author of any mischief of which the real perpetrator is not known. The cui bono was not invented by Cassius Severus, to whom it is ascribed,–but every man is alike the rock of the accused, in this respect.
If, therefore, it was natural, on general grounds, that Mr. Donnellan should be so suspected, it was also natural for him to be sensible that he would be so, and consequently, to be alarmed, distracted, and uneasy.
But it will be said, that, granting all this, he displayed more uneasiness than was even natural to one in his situation. It is a delicate thing to answer this question,–it is a nice thing to fix the standard of human feelings,–and to say what degree of perturbation a man, already branded with guilt and conviction, shall feel when placed under circumstances which make him to be suspected of a capital crime.
Lawyers, and those accustomed to see and advise with persons in that unfortunate predicament, only can tell the terrible apprehensions that every man feels at the idea of being a second time brought to a public trial; it is altogether a new view of human nature, and we seldom estimate, rightly, feelings which we have never experienced, nor expect to experience in our own persons, nor have witnessed in that of other persons;–
“To thee no reason,–
“Who good has only known and evil has not proved.”
They who have been accustomed to carry on criminal prosecutions, must be fully aware of the influence which a former trial and conviction is calculated to have on almost any accusation; but in no case can that influence be greater than where the trial turns on presumptive proof. For here it is often the feelings, the prejudices, and opinion of the jury, that supply the want of evidence.

Justice Francis Buller, who presided over the Donellan trial.
Suspicion is to be distinguished from proof,–a thousand suspicions do not form one proof. We understand, in common language, by the term suspicion, the imagining of something ill, without proof. It may, therefore, form a proper ground of accusation, but never of conviction: it seems to arise from the general semblance of things, and often from the morals of the individual, rather than from any distinct act. Thus, in the civil law, a guardian is regarded as suspected, whose morals render him so.
A suspicion is one thing, and a necessary inference another: a suspicion is an impression on another man’s mind,–an inference is made from the fact itself.
There certainly was no overt act proved against the prisoner during the whole course of this trial; it was not proved that he gave the poison, or saw it given, or had such in his possession. Many things, no doubt, in his demeanor and conversation, gave strong suspicions against him; but, if the civil law positively forbids a man being condemned on suspicion, can that be justified by ours?
“The wisdom and goodness of our law appears in nothing more remarkably, than in the perspicuity, certainty, and clearness of the evidence it requires to fix a crime upon any man, whereby his life, his liberty, or his property can be concerned: herein we glory and pride ourselves, and are justly the envy of all our neighbor nations. Our law, in such cases, requires evidence so clear and convincing, that every bystander, the instant he hears it, must be fully satisfied of the truth and certainty of it. It admits of no surmises, innuendoes, forced consequences, or harsh construction, nor anything else to be offered as evidence, but what is real and substantial, according to the rules of natural justice and equity.” * [*Lord Cowper’s speech on the Bishop of Rochester’s trial.]
We have been the more full in our observations on this trial, because it has been so often quoted with a sort of triumph, as forming a model and illustration of the nature of circumstantial evidence. It is an illustration, indeed, of how little evidence one man has been convicted on; but it is an illustration of nothing else.
–pp. xvii-xxvii.

Samuel March Phillipps, c.1826
Holmes, though not a lawyer, had a good grasp of the principles of English jurisprudence: probably garnered from the reading he had done while preparing for the unique career he created for himself, coupled with personal experience thereafter. But, one wonders what he DID read in this area?
Anyone recall any Canonical references that might help here?