If they are not security then they don't work for MS and have been assigned to watch her. God may have them there for a reason. Just something to think about.
They are working for the powers that be there, Greer and the rest. There is no mystery at all as to what there purpose is. God can do whatever He wills, but there is no mystery as to the fact that this force is there to make sure Terri dies, as per Greer's order.
I am thinking the same thing. Perhaps the police being there are part of God's plan on this. Heaven knows I can't see how this is going to work out.