Law 14: Goalkeeper and Penalties | IFAB Laws of the Game 2019/20

▼Brief overview▼
In the taking of a penalty kick, goal keepers are not permitted to stand in front of or behind the line. IFAB added that the goalkeeper must have at least part of one foot touching or in line with the goal line. This was done as its more practical approach and easier to identify if both feet are not on the line. As the kicker and ‘stutter’ in the run up, it is reasonable that the goalkeeper can take one step in anticipation of the kick.