Evidence law Lecture 3 (of 3) (Part 2): Impeachment, Privileges, and Expert Testimony

Impeachment, Privileges, and Expert Testimony

VI. Impeachment

A. Methods of Impeachment

Prior Inconsistent Statements

Used to challenge witness credibility.

Not hearsay if used only for impeachment.

Bias or Motive to Lie

Evidence showing a witness has reason to favor one side.

Conviction of a Crime

Felony or crime involving dishonesty may be used for impeachment.

Reputation for Untruthfulness

Witness’s general character for dishonesty may be attacked.

VII. Privileges

A. Attorney-Client Privilege

Protects confidential communications between attorney and client.

Exceptions:

If the client is seeking legal advice to commit a crime or fraud.

If the client waives the privilege.

B. Spousal Privileges

Spousal Immunity

A spouse cannot be forced to testify against the other spouse in criminal cases.

Applies only during the marriage.

Marital Communications Privilege

Protects confidential communications made between spouses during the marriage.

Survives divorce.

VIII. Expert Testimony

A. Qualifications and Reliability

Expert must have specialized knowledge beyond that of an average person.

Two main standards for reliability:

Daubert Standard (Federal & some states):

The theory/methodology must be peer-reviewed, tested, have a known error rate, and be generally accepted.

Frye Standard (Some states):

The methodology must be generally accepted in the scientific community.

B. Use of Expert Testimony

Must assist the trier of fact in understanding evidence.

Cannot state a legal conclusion (e.g., "The defendant was legally insane").

Cross-examination: Opposing counsel may challenge methodology, bias, or credibility.