In running the last half of the distance from home base to first base, while the ball is being fielded to first base, he runs outside (to the right of) the three-foot line, or inside (to the left of) the foul line, and in the umpire’s judgment in so doing interferes with the fielder taking the throw at first base, in which case the ball is dead; except that he may run outside (to the right of) the three-foot line or inside (to the left of) the foul line to avoid a fielder attempting to field a batted ball;
http://mlb.mlb.com/mlb/downloads/y2008/official_rules//06_the_batter.pdf
Interpret as you will...
