OKLAHOMA CITY, Oklahoma - A marketing expert testified in Oklahoma's opioid trial Monday, saying Johnson & Johnson's marketing materials were built to make patients and doctors feel their drugs were "safe and effective."

This marketing expert told the judge Johnson & Johnson used their marketing to educate people away from the message they didn't want them to hear.

Renzi Stone testified he looked at more than a thousand Johnson & Johnson promotional pieces. He said every single document he looked at talked about pain being "under treated," which has been a major focal point of the state so far.

The state said Johnson & Johnson "created the need" of under treated pain so they could sell to that need.    

Stone said, as a marketing expert, even he can't deny that the company's marketing strategy was impressive.

"We're all human beings, and we all like to think we're rational creatures," Stone said. "But marketing is about capturing both our intellect and our heart. Head and heart."

"I think the marketing plan was wildly successful," he said.

Stone said it's clear Oklahoma is a key market for the company.

The state of Oklahoma accuses Johnson & Johnson of trying to influence doctors to prescribe more of their medications.

"I didn't view this as they need to make sure they educate people," he said. "I viewed it as counter-education. Because in 2002, their competitor was having a lot of trouble in the media. Educating away from the message they didn't like."

Stone said, because the opioid crisis as we know it today took 20 years to create, he thinks it'll take at least 20 years to fix.