Metz added that Prince had no prescriptions in his name and the counterfeit Vicodin he took was not prescribed by a doctor.
"Prince had no idea he was taking a counterfeit pill that could kill him", the government official said.
Tyler says Thursday's announcement by a state prosecutor that no criminal charges would be filed in Prince's death affirms Johnson's innocence.
Schulenberg has agreed to pay a $30,000 fine to settle a federal civil charge that, according to Metz, has to do with writing a prescription under a false name.
Schulenberg prescribed Percocet to Prince on April 14, a week before his death, but wrote the prescription to Kirk Johnson, Prince's bodyguard, as a way to maintain Prince's privacy.
Prince, 57, was found dead at his Paisley Park home and recording studio complex near Minneapolis on April 21, 2016. Weeks after Princes death, agents found dozens of pills marked as prescription pain pills in Princes bedroom, inside two bottles of CVS-brand vitamin C tablets in a black suitcase. "As licensed professionals, doctors are held to a high level of accountability in their prescribing practices, especially when it comes to highly addictive painkillers".
The decision was announced by Carver County Attorney Mark Metz during a news conference on April 19.
Amy S. Conners, Schulenberg's attorney, said in a statement the settlement was made "in order to avoid the expense, delay, and unknown outcome of litigation".
US Attorney Greg Brooker, the top federal prosecutor for Minnesota, vowed to pursue other doctors for prescription abuse. Schulenberg was alleged to have prescribed controlled substances to one person despite knowing they were intended for another.
The report said the concentration of Fentanyl in Prince's blood was 67.8 micrograms per liter. The Star Tribune first reported that pills marked as prescription painkillers seized at the death scene were found to contain fentanyl.
Metz explained on Thursday that Prince had been taking counterfeit Vicodin pills that were laced with fentanyl.
While many who knew Prince over the years said he had a reputation for clean living, some said he also struggled with pain after years of intense performances. "But suspicions and innuendo are not sufficient in bringing criminal charges". Documents unsealed previous year paint a picture of a man struggling with an addiction to prescription opioids and withdrawal, and they also show there were efforts to get him help.
"I am mindful that is a most unusual and extraordinary case involving a world famous celebrity", Metz said.
A few days before he died, Prince was on his private plane heading home to Minneapolis from an Atlanta concert when he lost consciousness and his plane was forced to make an emergency landing in IL.
Eleven days before his death, Prince passed out on an airplane and had to be revived by a drug that counters the effects of an opioid overdoses. The day before he died his team reached out with an urgent request for help to an opioid addiction specialist, according to CNN.
Documents released by authorities a year ago paint a picture of a man struggling with an addiction to prescription opioids and withdrawal, and they also show there were efforts to get him help.