McKinsey has already paid close to a $600 million settlement for its consulting work with Purdue Pharma that fueled the opioid crisis. Now, as part of that investigation, new evidence has emerged about its role with other companies.

For example, McKinsey worked with Endo, which ramped up sales as part of a “blitz” recommended by McKinsey. In some cases, McKinsey suggested focusing on more potent products and, as we saw with Purdue, targeting physicians and developing aggressive sales incentive programs.

Endo sold Opana, which became an injected street-drug and caused an HIV outbreak. Still, McKinsey suggested ways to increase sales. McKinsey also recommended ways to avoid taxes, which, although technically legal, President Obama called tax “abuse.”

McKinsey promoted itself as having “in-depth experience in narcotics.” In one document, McKinsey boasted, “We serve the majority of the leading players.” That persuasive language has come back to bite the company.

Examples from the McKinsey document trove are included in 11th edition of Business Communication and Character to illustrate persuasive communication, writing style, and a lack of integrity. Newly released documents illustrate internal debate; for example, one consultant wrote, “We may not have done anything wrong, but did we ask ourselves what the negative consequences of the work we were doing was, and how it could be minimized?”

McKinsey may have hoped that the large settlement and public email to staff at the time would have ended the company’s trouble. But more criticism and lawsuits may be looming.