Unintended consequences of drug-testing beneficiaries

I've previously expressed concern that when a drug-testing regime is applied to Jobseekers but addicts are exempted, more beneficiaries will seek to be diagnosed as 'addicts'.

Expressing a similar concern is the Ministry of Health. In a Regulatory Impact Statement the following is contained:

 "The Ministry of Health (MOH) raised concerns with the drug testing proposals in Paper D. Their major concern is beneficiaries that fail drug tests will overstate their drug use to claim that they are drug dependent thereby avoiding financial sanctions. This in turn will lead to unnecessary referrals to drug addiction services, putting pressure on scarce resources."

Further MOH commented that:

"...the policy may result in a 'substitution effect' where some people substitute detectable drugs like cannabis, for drugs that are not detectable for as long such as alcohol or amphetamine-type substances, which may be more harmful."