This ease is before the law court on exceptions to the admission of evidence.
The action is assumpsit. It is founded upon a promise contained in a letter from the defendant, John Mussey, to his brother, Charles Mussey, dated Nov. 24, 1856. In that letter the defendant assured his brother that he might rely upon him for such pecuniary aid as would be necessary for his comfort and convenience; and he therein engaged to appropriate seven hundred dollars annually, to be paid to him semi-annually, for that purpose. The only question at the trial was whether this promise was gratuitous or founded upon a valuable consideration. The plaintiff had averred in her declaration that it was founded upon a valuable consideration, and the burden was upon her to prove such a consideration.
For this purpose she offered two papers signed by the defendant, dated December 1, 1838, — nearly eighteen years prior to the date of the defendant’s letter — by one of which the defendant agreed to account with Charles Mussey for whatever should be realized on a certain note therein described, and by the other to convey to him certain real estate upon his paying certain sums of money and performing certain other conditions therein mentioned. As these papers were not referred to in the defendant’s letter containing the promise on which the suit was brought, and did not appear to have any connection with it, they were objected to as irrelevant, but admitted by the court and allowed to go to the jury-
We think they should have been excluded. It is a fundamental rule governing the introduction of evidence that it must be rele*349vant; that is, it must have some tendency to prove or disprove one or more of the facts in issue. We think this evidence had no such tendency.
The only question was whether the defendant’s promise was gratuitous or supported by a valuable consideration. The consideration sought to be proved was the alleged compromise of the claims of Charles Mussey against his brother. Assuming that Charles had such claims against his brother, real or pretended,— and for the purposes of this inquiry it is not material which— what evidence is there in the case that the promise declared on was either made or accepted as a compromise of them ? Not a scintilla. The character of the promise, the language employed in making it, and the manner in which it was communicated to the promisee, all negative such a conclusion. A life annuity is not the usual mode of extinguishing business claims between persons sui juris. “ You may rely on me for such pecuniary aid as ■will bo necessary for your comfort and convenience,” is not the language of a debtor to a creditor. A letter from the debtor to the creditor is not the usual mode of prepetuating the evidence of a settlement. The evidence .would be in the hands of the wrong party. Besides, the letter on which this action is founded contains no allusion whatever to business transactions between the parties, nor to the settlement of any claims growing ont of business transactions, nor to the settlement or compromise of any claim or claims whatever. The inference to be drawn from the letter itself is that the promise therein contained was gratuitous, and not founded upon a valuable consideration ; and we fail to find a scintilla of evidence in the case which has the slightest tendency to repel this presumption. The evidence offered for that purpose was apparently irrelevant, and this apparent irrelevancy was not removed by any other evidence in the ease.
We have not overlooked the fact that in the trial of causes evidence apparently irrelevant often is, and, from the necessity of the case, must be admitted upon the statements of counsel that its pertinency will be made to appear by evidence afterward to be produced. But when this is done counsel must see to it at their peril that the connecting link in the chain of evidence is supplied ; *350for, if this is not done, and the evidence was seasonably objected to, its admission will be error, and cause for a new trial. To hold otherwise would virtually repeal the rule of law excluding irrelevant evidence.
The efforts to get before juries evidence which can have no other effect than to create in their minds some improper prejudice or bias, are constant, persistent, and too often successful. It is a practice which ought not to be encouraged. To hold that evidence apparently irrelevant may be received upon the statement of parties or their counsel that its relevancy will afterward be made to appear, and then allow it to remain in, when no such evidence is produced, and then hold that no peril is thereby incurred, would greatly encourage a practice which is already an existing evil, and virtually repeal a valuable and fundamental rule of the law of evidence.
We do not mean to say that a new trial should be granted for every inadvertent or accidental admission of irrelevant evidence. Such is not the law. If the court can see that the irrelevant evidence was perfectly harmless, — that it could not by any possibility have had any improper influence upon the jury — a new trial may properly be refused. But when, in addition to being irrelevant, it is of such a character as to be liable to mislead, confuse, or improperly influence the jury, a new trial should be granted. And such we understand to be the well settled rule of law. Ellis v. Short, 21 Pick. 142. Farnum v. Farnum, 13 Gray, 508. Brown v. Cummings, 7 Allen, 507. Ellingwood v. Bragg, 52 N. H. 488.
The documentary evidence to which we have referred, — we mean the two papers signed by the defendant, dated December 1, 1838 — was, at the time it was offered by the plaintiff, apparently irrelevant to the issue being tried ; it was seasonably and specifically objected to by the defendant upon the ground of its irrelevancy ; its apparent irrelevancy was not removed by any other evidence produced at the trial; in addition to its irrelevancy, it was such evidence as would be liable to influence the jury improperly; they were not instructed to disregard it, but, on the contrary, were told that they might take it into consideration in *351determining whether or not there was a legal consideration for the promise declared on. Its admission, under these circumstances, was, in the opinion of the court, such an error as entitles the defendant to a new trial.
Exceptions sustained.
New trial granted.
Appleton, C. J., Barrows, Yiroin, Peters and Libbey, JJ., concurred.