Mandatory Slide Rule

This is how the rule is worded in our official section of local rules at Mathewson-McCarthy Babe Ruth baseball.

The slide rule (collision avoidance rule)-- The SLIDE RULE (COLLISION AVOIDANCE RULE) will be in effect for all divisions. This rule is in force for any runner at any base where the ball is in the glove (in possession) of the fielder and he is attempting to make a tag. In this instance, THE RUNNER MUST SLIDE OR ATTEMPT TO AVOID A COLLISION WITH A FIELDER. If not, the runner is declared out.

If a deliberate attempt to injure is determined by the umpire, the runner is ejected from the game and a report must be made to the Board of Directors for further disciplinary action.

It should be noted that a fielder while NOT in possession of the ball and not attempting to field the ball, may be guilty of obstruction if that fielder impedes the progress of a runner. It is entirely up to the judgement of the umpire as to whether a fielder is in the act of obstructing a runner.

That's how we word it, in practice it has been expanded that if the fielder is waiting for the throw at the bag or plate, the runner slides. Hope this helps.