"But of course the Parliament's got to provide those powers to the police."
English and Bennett announced the $82 million drug addiction package at Higher Ground, a drug rehabilitation centre in Te Atatu, yesterday.
"Meth is a scourge, its a growing scourge, in more communities and among younger people," English said.
Half of the four-year funding package would go into cutting off drug distribution and penalising gangs involved in drug dealing.
If National gets back in to power, there would be higher penalties for manufacturing and distributing synthetic cannabis - from two years to eight years. Penalties would not rise for possession.
Gang members on a benefit who could not explain expensive assets would have their welfare cut.
National also wants to target drug supply chains, both international and domestic.
Compulsory police vetting would be introduced for anyone working at ports, mail centres or airport baggage centres. Drug dogs would be used at ports, mail centres and domestic airport terminals, not just international terminals.
English said there was some carrot to go with the stick. Half of the funding would go towards health, education and prevention services.
"We want to be clear that where people are on methamphetamine, there is the opportunity for rehabilitation."
The funding boost would create 375 more places a year in drug rehab clinics. That would nearly double existing national capacity, English said.
Higher Ground's director, Johnny Dow, said any new funding for rehab was valuable. The waiting list for his centre was currently around 14 weeks, for an intensive 18-week programme.
He said the treatment centre had seen an increase in admissions for meth use, especially since 2014. An addict's average costs were between $300 and $3000 a week - costs so high that users needed to commit crime.
"There's generally about 70 on the waiting list at any one time. If people were coming from prison as well - we don't take them all because we like to take people from the community - it would be up around 200."
He highlighted some disturbing trends, such as a rise in people injecting meth, alcohol addicts using meth to "get them out into the world faster" and people combining meth and the drug known as GHB, a date-rape drug. "One drug takes them up and the other calms them down."