The criminal conviction assessment authorized by Government Code section 70373, subdivision (a)(1) does not constitute a prohibited ex post facto law. Section 70373, subdivision (a)(1), effective on January 1, 2009, requires imposition of a $30 assessment for each misdemeanor or felony offense. The appellate division of the superior court held that imposition of the fee for an offense predating the effective date of the statute does not result in prohibited ex post facto law for the following reasons: the stated purpose of the statute is to fund court facilities, not to punish; the statute is part of a broad legislative scheme in which civil fees were also raised to fund courthouse construction; it is termed an assessment, not a fine or penalty; it is a relatively small amount; and the amount is not dependent on the seriousness of the offense. The judgment was affirmed but remanded for imposition of the assessment on all the convicted offenses because the court imposed only one assessment.