A friend of his son is in great trouble with the police. He is going to be taken away by them. In fact a policewoman and a policeman are waiting in the kitchen area of the house to take him away. But he does not have proper black pants to wear so he can leave with them. The dreamer is offering the young man to take his black trousers - quite a few of which are there - but everyone of which when he puts on does not quite fit him. It looks like he is purposely not trying to get in them readily and then he is also doing some wasteful activities instead of putting on those pants the way he should and leaving with the police. This is making the dreamer angry that the kid is incompetent and will not amount to anything.
The day before the dreamer had been going through his closet and had noticed how many of his black trousers that no longer fitted him were fitting him now and the ones which fitted him well till recently were now too loose because of the weight loss and it had taken him some time to decide which pants to wear and while he was sifting through those black clothes the thought had passed his mind that soon he will be wearing none of them.
In the dream this process of deciding upon which black trousers to wear had been projected upon his son's friend and turned into an accusation that he is incompetent and will not amount to anything. Since black as much as white shroud or cloth symbolizes death, the black trousers symbolized it and which the dreamer was trying to escape by pushing it upon the young lad and getting angry and accusing him of incompetence for not readily accepting it. The two police were agents of death who had come to take him away but which the wish fulfillment had shifted it to the young man that he is the one in trouble with the police (death) not me. The accusation of incompetence was actually reversal of the realization that the young kid is too smart to be pressured into accepting the fate of the old man upon himself.