KEY POINTS:
More than 100 prisoners have tested positive for drugs while in a drug-free unit, National's corrections spokesman Simon Power said today.
An answer to a parliamentary question showed that in the first nine months of the 2006/2007 financial year 115 prisoners tested positive for drugs while in one of the Corrections Department's drug-free units.
Almost 200 tested positive in the 2005/2006 year.
Mr Power called on Corrections Minister Damien O'Connor to explain how people were "getting their fixes" in the units.
"I understood these units were supposed to be as their title suggests - drug-free," he said.
"Presumably prisoners go into these units to kick their habits, But if these figures are correct, a good proportion of them do not seem to be achieving anything like the desired effect."
A spokesman for Mr O'Connor said it was important to note that the percentage of positive tests had more than halved since National was in power.
In the 05/06 year the percentage of positive tests was 12.97 per cent, compared with 27.24 per cent in 98/99 under a National government.
So far this year the percentage of positive test was 9.02 per cent.
It was a "difficult environment" and there had been a lot of progress in intercepting contraband coming into prisons, he said.
"We have invested a lot and we're seeing results from that, because the numbers are coming down," he said.
- NZPA