pick off move

Question
Runner at first.  Left handed pitcher.  Pitcher gets the sign and comes set.  Without stepping back off the rubber or stepping towards first base the pitcher throws over to first.  Is this legal?

Answer
Alan,

No, this is not legal. The pitcher must step with his non-pivot foot toward the base he is throwing to. Most umpires are instructed to look for "distance and direction" toward the base. In other words, the non-pivot foot must move closer to the base at an angle that is more toward the base than any other base.