Facts are central to any legal decision. Only once the facts of the matter have been determined by the court can the relevant law be applied and a decision rendered. The basic rule of evidence is that information can be admitted as evidence where it is relevant to a material issue in the case. Other rules of evidence deal with the exclusion of evidence from being considered by the court or tribunal. An example of such an exclusion is legislation on apology which prevents an apology from being introduced as evidence.

Types of Evidence

The primary ways evidence is put before a court or tribunal are verbal testimony of the people involved, documents, and the opinions of expert witnesses.


Oral testimony is given by parties to the case, such as plaintiffs, defendants, complainants, and respondents. It is also given by witnesses, who are persons without legal interests at stake in this proceeding but with information relevant to the legal issues to be decided. In order to impress the gravity of the situation on people about to testify, they are required to swear an oath or make an affirmation as to the truth of what they are about to say. Testimony will be tested for its reliability by questions put to the person, most commonly by lawyers, though the judge or panel may also pose questions.


Although not the only document used as evidence, the patient's health record can be extremely important to a case's resolution. The health record should provide a factual chronology of events, given its function as a communication tool for health care providers, for the benefit of the patient. Criteria used by the court to assess the reliability of chart entries are that they were made: contemporaneously to the care given; by the person who had personal knowledge of the events; and by a person who had a duty to record the events.1 Witnesses or parties to the proceeding may prepare to give evidence by reviewing documents such as the patient's chart to refresh their memories. Interestingly, the plaintiff 's lawyer and defendant's lawyer will be using the same documents to try to prove opposing facts.

Expert witness opinion evidence

Unlike factual witnesses, expert witnesses testify as to their opinion about some element of the case.2 They cannot testify about what happened at the time because they were not there. The chart is a prime source of data for the formation of expert witness opinion evidence. If a court decides that the chart is unreliable, it brings into question the reliability of expert witnesses opinions since the foundation for the opinions has been deemed to be flawed.

Admissible Evidence

To be admissible, evidence must be: reliable; relevant to an issue in the case; and not subject to an exclusionary rule of evidence. The rule against hearsay is an exclusionary rule and it provides an example of the complexity of the rules of evidence. Hearsay is evidence (such as testimony) of a statement made to a witness or party by a person who will not be called as a witness, put forward as the truth of the statement. There are many exceptions to the hearsay rule. It is not hearsay to introduce an out-of-court statement to establish the fact that the statement was made. A nurse who is giving evidence can simply identify what was said to her and by whom. Then a legal determination as to the admission of this hearsay evidence will be made by the court after the lawyers have presented their legal arguments about its admissibility.


Once a court has decided evidence is admissible, it will determine how much weight it has, in other words, evaluate its significance in relation to other evidence. This is not a mathematical calculation. To use the patient's chart as an example, the weight given to it may be based on a number of factors such as frequency of entries, level of detail, accuracy of times and events, presence or absence of alterations, and omissions of information relevant to the patient's care at the time.

Formality of Legal Process and the Rules of Evidence

The process of civil litigation is governed by provincial and federal statutes which set out the rules of court. An example is the requirement for early disclosure of relevant documents between the parties to encourage early resolution of the dispute. The rules of procedure and rules of evidence are less formal for an administrative tribunal such a panel hearing a professional discipline case but they still exist.

Preservation of Evidence

The resolution of a legal dispute can take place years after the originating incident. While the patient's health record may be the best evidence of your good nursing care, it is the property of the health facility and must be accessed and used only in accordance with law. Preserving your evidence by writing down what you know of the event can ensure it is not lost or varied with the passage of time. High quality evidence will positively affect your credibility. To preserve your evidence while maintaining solicitor-client privilege,3 the document must be a communication to a lawyer in anticipation of legal proceedings. Nurses who wish to preserve their evidence may seek assistance from the institution's risk management or legal department. The Canadian Nurses Protective Society can help a nurse preserve her written evidence. Physical evidence, such as a patient's clothing or bullets, may have to be preserved for future legal proceedings. Health institutions should direct their staff by having a policy on the preservation of physical evidence.

Our legal system strives to achieve fair resolutions to disputes. Nurses who give evidence can contribute to this goal by providing the court with high quality evidence thereby helping ensure its judgments are as fair as possible.

  1. Ares v. Venner, [1970] S.C.R. 608.
  2. infoLAW, Expert Witness (Vol. 15, No. 1, March 2006).
  3. infoLAW, Privilege (Vol. 9, No. 1, April 2000).

N.B. In this document, the feminine pronoun includes the masculine and vice versa except where referring to a participant in a legal proceeding.


Vol. 18, No. 2, December 2009

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