Northern Coast Officials
Gerry Davis
Umpire Attire
D1 Sports Apparel
Shot Clock Rules and California Modifications
Introduction Rules governing the use of a shot clock for high school basketball in California are the same rules that govern the shot clock in NCAA.

The shot-clock periods are:

  • 30 seconds for girls.
  • 35 seconds for boys.
The following is guidance for high school officials to correctly manage and interpret the shot-clock rules.
Violation Occurs The team in control shall attempt a try for field goal within the allotted shot-clock time.

The try shall leave the player’s hand before the expiration of the allotted shot-clock time.  Following the release, the try subsequently shall strike the basket ring or enter the basket before or after the expiration of the allotted shot-clock time.

The ball becomes dead when the violation occurs.  The ball is awarded to the opponent for a throw-in at the out-of-bounds spot nearest the violation.
Shot-Clock Operator The shot-clock operator shall control a separate timing device with a horn that shall have a sound distinct and different from that of the game clock.

The shot clock is used for the entire game, including overtime periods.

An alternate timing device shall be available.

Starting the
Shot Clock
When stopped the shot clock will be started when:
  • An inbounds player touches the ball following a throw-in.
  • A team first gains possession of the ball following a:
    • Jump ball.
    • Rebound on a try that hits the rim.
    • Loose ball.
Stopping and Continuing Time The shot clock will be stopped and the offensive team shall have the unexpired time remaining on the shot clock to attempt a shot when play continues:
  • Following a time-out.
  • Following a deflection out-of-bounds by a defensive player.
  • Following an official’s time-out for an injured player.
  • Following an official’s time-out for a player who loses a contact lens or glasses.
  • Following a held ball and the offensive team retains possession of the ball by the AP arrow procedure.
Resetting the Shot Clock

The shot clock will be reset when:
  • Team control is established after the opponents lose possession of the ball.
  • The mere touching of the ball by an opponent does not reset the shot clock if the same team remains in control of the ball.
  • A foul occurs, exception: double foul, double technical, simultaneous foul.
  • A held ball occurs and the defense is awarded the ball through the alternating-possession arrow procedure.
  • A try for the goal is attempted and the ball hits the rim.
  • A violation occurs.
    Most violations are by the offensive team causing a change of possession and the shot clock is reset.
  • The defense commits a violation by:
    • Kicking the ball.
    • Striking the ball with a fist.
    • Knocking the ball through the underside of the basket.

NOTE: New College reset rules in regards to a kicked ball DO NOT apply to high school rules in California.

Expiration of the Shot-Clock Period The horn shall sound at the expiration of the shot-clock period.

The horn does not stop play unless recognized by an official's whistle.

If the shot clock shows 00 but the horn has not sounded, time has not expired.

Shot Clock Continues to Run The shot-clock will continue running:
  • During a loose ball situation:
  • When the offense regains possession.
  • When the ball is thrown at the wrong basket.
  • When a try is attempted but does not touch the rim.
Turn Off the Shot Clock The shot clock shall be turned off when the game clock shows less time than a shot-clock period.
Doubt If there is doubt whether a try for goal was attempted before the horn, the final decision shall be made by the game officials.
Shot Clock Official's Signals
...then... ...then...
Stop Clock   Shot Clock Violation   Direction Signal
Instructions to the Shot-Clock Operator (1) Boys’ Game: 35-seconds.
(2) Girls’ Game: 30-seconds.
(3) Four times the shot clock is reset:
  • Try for goal hits rim.
  • Foul.
  • Change of possession: Defense must be holding or dribbling ball.
  • Bad defensive play violations: Kicking ball, batting ball or knocking ball through bottom of basket.
(4) If you are not sure - do not reset the shot clock.
(5) Starting the shot clock:
  • Throw-ins: When the ball is touched on the court.
  • Free throws and Jump Ball: When a team gains control.
California High School Modifications
Introduction Three rule modifications are used from the National Federation rulebook for high school basketball in the state of California.  They are:
  • “Closely guarded player” rules.
  • No 10-second count applied to cross the division line.
  • Mercy Rule.
Closely Guarded Rules for Girls In a Girls' game, a player shall not while closely guarded anywhere on the entire court:
  • Hold the ball without dribbling for 5 seconds.
  • Control, hold or dribble, the ball for 5 seconds in an area enclosed by screening teammates.
Division Line and Backcourt There is a division line.

The following rule is not in effect for Girls’ games:

  • 10-second backcourt count.

The following rules are in effect for Girls’ games:

  • Over-and-back.
  • Frontcourt and backcourt definitions.
Mercy Rule When at the conclusion of the third quarter, or any point thereafter, if there is a point differential of forty (40) or more points, a running clock shall be instituted for the remainder of the game, regardless of the score.

Example: 4th quarter "mercy rule" in effect. Point differential drops below 40 points - clock keeps running.

  • Clock will stop for time-outs and injuries.
  • This applies to all levels of high school play.