If (during play) a fight breaks out between 2 opposing players. you (as center ref) blow the whistle for the fight. Neither you nor the AR saw who started the fight, you Red Card BOTH players.
Which would be the restart?
1. Restart where the ball was at the time you blew the whistle with an IFK to the team that had possession of the ball
2. Drop ball at the point of the Serious Foul Play
3. IFK at the point of the SFP to a team of your choice (just like choosing a team for a throw in that went out and you could not determine who last touched the ball)
4. DFK at the point of the SFP to a team of your choice (just like choosing a team for a throw in that went out and you could not determine who last touched the ball)
USSF answer (May 7, 2008):
The Federation has stated quite clearly that the referee must make a decision in all cases of infringements of the Laws, if that is at all possible. If it is not possible to determine who began the fight and both parties appear to be equally involved, then the correct restart is a dropped ball at the place where the ball was when play was stopped, bearing in mind the special circumstances involving the goal area.
If the nearer AR has not seen the incident, it never hurts to ask the AR who is farther away (or the fourth official, if there is one).