A schoolbus driver was taken to court for grabbing the arm of a rowdy boy who would not stop pulling a girl's hair.

But the judge threw out the charge - and had a policeman take the 12-year-old boy to the police cells as a warning.

Jim McCorkindale, 70, of Gore in Southland, told the Weekend Herald that while dropping off children last July, he saw two boys pulling the hair of a girl and got out of his driver's seat to try to stop it.

"I went over and touched the boy on the arm to attract his attention, and that was the assault."

When the boy did not respond to being told to stop, "I threatened to hit him in the ribs, and he flinched and let the kid's hair go to protect his ribs", Mr McCorkindale said.

"But I never touched him again."

The boy had continued misbehaving after Mr McCorkindale returned to his seat.

Children on the bus called the police and he found officers waiting to talk to him when he finished his run.

When police rejected the option of diversion, Mr McCorkindale received a court summons.

But in the Gore District Court, Judge Kevin Phillips threw out the charge.

Instead, he told the boy he should be "thoroughly ashamed" of himself and had a policeman take him to the cells, the Southland Times reported.

Mr McCorkindale said he found it disgusting that he was charged in the first place.

"You can't do a bloody thing," he said. "It's better to hop out of the bus and leave them to it. See nothing.

"The days of sit down, shut up, do as you are told, are gone. When I was going to school, you did what you were told. Now, you sometimes do as you're asked - if it suits you."

The Weekend Herald approached police yesterday about the decision to charge Mr McCorkindale, but officers spoken to said they were unable to comment.

Mr McCorkindale, whose wife died at Christmas, said: "I suppose they have got their ways of doing things. But it's not my idea of fairness.

"It was straight-out bloody ridiculous, in my opinion. I was a little bit concerned, not so much for myself, but for my invalid wife who was with me at the time."

Mr McCorkindale said that although the charge had been dropped, he was still left with legal bills, and had no idea how he was going to pay them.

"The [boy] who caused the trouble, he gets off scot-free. The police were doing his work."

Although the boy had apologised, Mr McCorkindale said the message from the judge "wouldn't mean a damn thing to him".

He said he was now considering quitting driving the schoolbus.