Key Legal Concepts: Evidence and Witnesses

Relevance

Evidence is relevant if it has any tendency to make a fact of consequence more or less probable.

Probative Value

The ability of evidence to prove something important in a court case.

Prejudicial Evidence

Evidence that may unfairly sway the jury or judge against a party.

Character Evidence

Evidence used to show a person's character traits, typically inadmissible to prove conduct.

Defendant's Character

In criminal cases, the defendant may introduce evidence of their good character.

Victim's Character

The defendant may introduce evidence of the victim's character, which can be rebutted by the prosecution.

Habit Evidence

Evidence of a person's routine practice or habit that is admissible to prove conduct in conformity with that habit.

Hearsay

An out-of-court statement offered to prove the truth of the matter asserted.

Non-Hearsay

Statements offered for purposes other than the truth, such as effect on the listener.

Prior Inconsistent Statements

Statements made by a witness that contradict their current testimony, admissible for impeachment.

Admissions by a Party-Opponent

Statements made by a party that can be used against them in court.

Hearsay Exceptions (Unavailable Declarant)

Certain statements that can be admitted even if the declarant is unavailable, like dying declarations.

Present Sense Impression

A statement made while perceiving an event, admissible as an exception to hearsay.

Witness Competency

Witnesses must have personal knowledge and take an oath or affirmation to testify.

Impeachment

The process of challenging the credibility of a witness.

Bias or Interest

Evidence showing a witness may have a motive to lie.

Character for Truthfulness

Evidence of a witness's reputation for honesty, admissible for impeachment.

Criminal Convictions

Felonies may be admissible if their probative value outweighs the prejudicial effect.

Expert Witness

A witness qualified by knowledge or experience to provide specialized testimony.

Attorney-Client Privilege

Protects confidential communications between an attorney and their client.

Spousal Testimonial Privilege

In criminal cases, a spouse cannot be compelled to testify against the other.

Physician-Patient Privilege

Protects communications made for medical diagnosis or treatment.

Authentication

The process of proving that evidence is what it claims to be.

Best Evidence Rule

Requires the original document to be presented when its contents are at issue.

Judicial Notice

A court's acceptance of a fact as true without formal proof if it is generally known.

Presumption

A legal assumption that a fact is true until disproven.

Burden of Proof

The obligation to present sufficient evidence to support a claim.

Preponderance of the Evidence

The standard of proof in civil cases, meaning more likely than not.

Beyond a Reasonable Doubt

The standard of proof in criminal cases, requiring a high level of certainty.

Daubert Standard

Criteria for the admissibility of expert testimony based on reliability and relevance.