cfest notes #`1

Principle of legality

A person cannot be punished for conduct unless the law made that conduct criminal before the person committed it.

Statutory law

Created by legislatures and written in statutes. (example: criminal codes)

Common law

Developed through judicial decisions and established through prior cases

Model penal code

A model set of criminal laws, but it is not automatically binding law. A jurisdiction must adopt its provisions.

Common law important purpose

Courts can use common law to help interpret statutes, especially when a statute does not define every term.

Khaliq case important takeaway

Common law can adapt to new circumstances.

Common law can develop to address new situations without necessarily creating an entirely new crime.

Common law is flexible.

Keeler v. superior court

Courts cannot unexpectedly expand criminal statutes to punish conduct that was not previously covered.

Writ of prohibition

An order issued by a higher court that stops a lower court from doing something it does not have the legal authority to do.

A writ of prohibition is basically a higher court telling a lower court:

"Stop! You do not have the legal authority to proceed with this."

Ex post facto laws

Making an action that was legal when it was committed a crime; or

Increases punishment for past conduct.

Criminal legislation generally cannot retroactively criminalize previously lawful conduct.

Rule of lenity

When a criminal statute remains genuinely ambiguous after applying the usual tools of interpretation, courts generally interpret the ambiguity in favor of the defendant.

Unresolved ambiguity in a criminal statute generally favors the defendant.

Important comparison between common-law interpretation and statutory-law interpretation

Common-law approach:

Court allowed existing law to cover new circumstances.

Emphasizes flexibility.

Statutory-law approach:

Court refused to expand the statute's established meaning.

Emphasizes fair warning and legality.

Both involve new circumstances that existing law did not expressly address. However, the courts reached different results because of their different approaches to interpreting and developing criminal law.

This illustrates the tension between allowing criminal law to evolve and protecting defendants from unexpected criminal liability.