BUFFALO, N.Y. — Four new K9 officers will join the Erie County Sheriff's Office later this year, but the unit isn't expanding. Instead, the dogs are replacing four that are being forced to retire due to potential legalization of recreational marijuana.

"They're a great asset to law enforcement," said Scott Zylka, public information officer for the Sheriff's Office, which has a dozen and a half K9s with different specialties.

"We have explosive detection, narcotics detection. We have an accelerant detection, and we have a cadaver dog. On top of that, we have two therapy dogs," Zylka explained.

Only the narcotics dogs are being forced into retirement.

Court rulings in states with legal cannabis found if a drug-sniffing dog is trained on marijuana, officers would need more probable cause to search a vehicle without permission.

"We can't get probable cause for us to search the car, and that is the key thing that these dogs are for," said Officer Brian Laas with the Arvada, Colorado Police Department.

The four E.C.S.O. dogs that are retiring will get to stay with their handlers.

"That's a big deal for the handlers," Zylka said. "Not only is it a partner, but it becomes somewhat of a family pet."

The new K9s collectively cost about $40,000, which doesn't include expensive training. The E.C.S.O. used drug forfeiture money to make the purchase.

Training for the new K9s will start relatively soon and could take up to 6 months to complete.