New Zealand needs to overhaul laws governing the compulsory treatment of severe alcoholics and drug addicts, says the Law Commission.

The commission has reviewed the Alcoholism and Drug Addiction Act 1966 and concluded it is outdated and reform is long overdue.

The 1966 act gives powers to compulsorily detain alcohol and drug addicts in institutions for assessment and treatment but there were difficulties in reconciling its broad powers of detention with the rights and protections under the Bill of Rights Act.

There were problems with who could issue the two medical certificates needed, difficulties getting District Court applications and the statutory detention period was two years, far longer than necessary for treatment.

Also there were only a few treatment facilities available and little flexibility in the type of treatment available.

The commission concluded that compulsory treatment was only justified where a person's dependence was seriously impaired, where it was necessary to protect them, could benefit them, they refused treatment or no other less restrictive means was available.

It recommended the Act be repealed and replaced with a new regime for the compulsory treatment of people suffering from severe substance dependence.