How involved should you become

I believe it was a great official on this board that said a foul in the first min is a foul in the last min no matter what the score or situtaion. As coaches all we want is the game to be called the same the whole game. I'm concerned that things an official would not normally call would be called or that calls would be purposely made on just one team because of the score. Please explain to me in the interest of fairness and your job to up hold the law of basketball where this fits in. Also thanks to everyone that has posted that has given me new ways to look at this.