
149 S.E.2d 22 (1966)
267 N.C. 707
Marion Ruth PEARCE
v.
Beulah P. BARHAM, Administratrix of Calvin W. Barham, Deceased, and Dolly Barham.
No. 527.
Supreme Court of North Carolina.
July 6, 1966.
*25 Everett, Creech & Hicks, by Robinson O. Everett, Raleigh, for plaintiff appellant.
Dupree, Weaver, Horton, Cockman & Alvis, by F. T. Dupree, Jr., Jerry S. Alvis, Raleigh, for defendant appellees.
HIGGINS, Justice.
Three issues were raised by the pleadings: (1) Did the plaintiff suffer injury and damage as a result of the defendant's negligence? (2) Did the plaintiff, by her own negligence, contribute to her injury? (3) What damage, if any, is the *26 plaintiff entitled to recover? Only evidence which had bearing on these issues and tended to aid the jury in finding the proper answers to them should have been admitted at the trial. Rules of evidence furnish the guidelines by which the presiding judge shall determine what shall be admitted to the jury for its consideration in finding the answers to the issues. Gurganus v. Guaranty Bank and Trust Co., 246 N.C. 655, 100 S.E.2d 81; DeBruhl v. State Highway and Public Highway Commission, 245 N.C. 139, 95 S.E.2d 553.
The law recognizes that evidence, when of slight value, may be excluded because the sum total of its effect is likely to be harmful. Stansbury states the rule: "Even relevant evidence may, however, be subject to exclusion where its probative force is comparatively weak and the likelihood of its playing upon the passions and prejudices of the jury is great." N.C. Evidence, 2d Ed., § 80, p. 175. "There is a fundamental postulate of evidence that circumstances which are irrelevant to the existence or nonexistence of the disputed facts are not admissible. * * * The details of bad and questionable conduct * * * were paraded before the jury. * * * The result seems to have carried the jury too far from the critical question involved; that is, the fair and just compensation for the pecuniary injuries resulting from death." Sanders v. George, 258 N.C. 776, 129 S.E.2d 480; Modern Electric Co. v. S. E. Dennis, 259 N.C. 354, 130 S.E.2d 547; Godfrey v. Western Carolina Power Co., 190 N.C. 24, 128 S.E. 485.
The court, over objection, permitted the defendant to introduce evidence of the son and daughter which paramounted issues not raised by the pleadings. The harmful effect is obvious. The relevant facts in this case are those which bear on the intestate's negligence, the plaintiff's contributory negligence, and the plaintiff's damages.
By introducing evidence tending to show the intestate forced the plaintiff to re-enter the Ford just before the accident, the defendant contends that evidence of prior associations and relationships became admissible as tending to show the plaintiff was not a captive at the time of the accident. The weakness in the argument is two-fold: (1) There is no allegation and no issue raised that the plaintiff was other than a passenger. (2) Prior conduct disassociated from the operation of the vehicle was not the test by which to determine negligence or contributory negligence in causing the wreck. The plaintiff was married and living with her husband. The intestate and his personal representative were separated. The evidence tended to permit the jury to try the parties rather than the issues raised by the pleadings.
Conceding the defendant was within her rights in cross-examining the plaintiff with respect to her relationships with the intestate on the ground that it tended to impeach her testimony as a witness, nevertheless these were collateral matters, and her answers were conclusive. "Ordinarily, the answer of a witness on cross-examination concerning collateral matters for purposes of impeachment is conclusive, and he may not be contradicted by other evidence." In Re Gambell, 244 N.C. 149, 93 S.E.2d 66; State v. Roberson, 215 N.C. 784, 3 S.E.2d 277.
The defendant may not contend the evidence of the son and daughter was admissible to contradict the plaintiff on the collateral subject of prior relationships of the parties. The only defense to an action for damages resulting from actionable negligence is the contributory negligence of the injured party which was a participating cause of the accident and the resulting injury.
The plaintiff's counsel contends the court committed error in permitting the defendant to read to the jury the adverse examination of Dolly Barham taken by the plaintiff when she was attempting to find out whether the intestate was Dolly Barham's agent at the time of the accident. The grounds *27 of the objection are: (1) Dolly Barham was no longer a party. (2) The remaining defendant was not present and did not participate in the adverse examination. (3) The plaintiff did not offer any part of the examination. (4) Dolly Barham at the time was present in court and available as a witness.
Conceding, without deciding, the defendant, under the circumstances, had the right to use the adverse examination, thereby presenting to the jury Dolly's version as to the fight going on between the plaintiff and the driver, and her efforts to get the keys from the switch of the speeding automobile, by so doing, she opened the door, giving the plaintiff the right to present her version of the episode to the jury. Having read the adverse examination to the jury, the defendant is estopped to deny its admissibility. "The law that an interested survivor to a personal transaction or communication cannot testify with respect thereto against the dead man's estate is intended as a shield to protect against fraudulent and unfounded claims. It is not intended as a sword with which the estate may attack the survivor. * * * In offering the evidence of Howard Carswell and objecting to the evidence of Dennis Greene, the plaintiff sought to pick up the shield, [after] having first used the sword. This the law does not permit." Carswell v. Greene, 253 N.C. 266, 116 S.E.2d 801. The deceased's personal representative testified. She offered the adverse examination of Dolly Barham as to the acts and conduct both of the deceased and of the plaintiff up to and including the accident. The defendant opened the door to the extent the plaintiff was entitled to be heard and to give her version of the transaction described by Dolly Barham. G.S. § 8-51; McCurdy v. Ashley, 259 N.C. 619, 131 S.E.2d 321; Hayes v. Ricard, 244 N.C. 313, 93 S.E.2d 540; Batten v. Aycock, 224 N.C. 225, 29 S.E.2d 739; Sumner v. Candler, 92 N.C. 634. "There is nothing inequitable in requiring that the opposing testimony to that given in evidence by the other side should be limited to the same transaction or communication." Walston v. Coppersmith, 197 N.C. 407, 149 S.E. 381.
Because of the errors here discussed, we conclude the plaintiff should have a
New trial.
MOORE, J., not sitting.
