All states have laws that prohibit drivers from making an illegal or improper turn. Common examples of illegal or improper turns are:

• U-turns (when there is a No U-Turn sign)

• Making a right or left turn without first moving to the far right or left lane

• Making a right or left turn when there is a sign at the intersection that prohibits such turns (No Right Turn).

The penalty for making an illegal or improper turn usually includes a fine and points on your driver’s license.

As with many traffic violations, the officer issuing the citation and the prosecutor have significant discretion in determining whether there was a violation of a traffic law and whether the violation constitutes a certain offense, as defined by the state legislature in the traffic code or in a municipal ordinance.

This discretion to issue a ticket or citation and prosecute the charge against the driver is balanced by the discretion of the jury or judge in determining whether the prosecution met its burden of proof sufficient to convict the driver (for a criminal offense) or find the driver responsible (for a civil infraction, violation, or offense).

In California, traffic laws strictly regulate turns to ensure road safety. Illegal or improper turns include executing a U-turn where it is prohibited by signage, turning without moving to the appropriate lane (far right for right turns, far left for left turns), and making turns where signs indicate they are not allowed (e.g., No Right Turn). Violating these regulations typically results in a fine and may also add points to the driver's license, which can lead to higher insurance rates and, with enough points, license suspension. Law enforcement officers have the discretion to issue citations for these violations, and prosecutors decide how to charge the offense. If the case goes to court, the judge or jury will determine if the prosecution has proven the case beyond a reasonable doubt for criminal offenses, or by a preponderance of the evidence for civil infractions. The specific penalties and process for contesting a ticket can vary depending on the local jurisdiction within California.