Collie police have been reprimanded for leaving a drunken 15-year-old boy soaked in urine in a police van for 2½ hours on a cold winter night with hypothermia closing in.
The "disturbing" incident was revealed in a report by the Parliamentary Inspector of the Corruption and Crime Commission, who said it was "regrettable" the watchdog had failed to follow up the 2011 incident for two years.
Retired Supreme Court judge Michael Murray's report revealed the boy, who had been arrested for an undisclosed reason but had not been disorderly, was left in the van because officers claimed it was warmer than the station.
The officers argued that it would be better for him to be kept upright in case he vomited.
The boy remained in the van until his parents arrived from Mandurah to collect him.
He was wet from urine and had vomited. When he was taken to Collie Hospital his body temperature was 35.5C - half a degree above when hypothermia sets in.
The CCC referred the complaint to WA Police for internal investigation in August 2011 but because the commission incorrectly categorised the case, did not monitor its progress until September last year.