An anti-drugs lobby group says the small number of police surveyed for a two-year review of drug-driving measures casts further doubt on the review's credibility.
The Ministry of Transport prepared an eight-page report for Cabinet on the roadside impairment test regime - with half of it either background information or detailing why New Zealand shouldn't move to saliva-based testing.
Information obtained under the Official Information Act by Radio New Zealand News shows 35 officers were surveyed.
While 24 found the regime easy and workable, seven considered it drawn-out or subjective.
Campaign Against Drugs on Roads co-ordinator Rachael Ford says the sample size is a joke and adds nothing of value to the report.
Ms Ford says the Cabinet was remiss in accepting a report that lacks evidence on whether drug-driving is reducing or increasing.
Associate Transport Minister, Simon Bridges, has been unavailable for comment.