Carver County Attorney Mark Metz's announcement on no criminal charges came just hours after documents revealed that a doctor who was accused of illegally prescribing an opioid for Prince had agreed to pay $30,000 to settle a federal civil violation. Prosecutors alleged Dr. Michael Todd Schulenberg wrote a prescription for oxycodone in the name of Prince's bodyguard, intending it to go to Prince.
Metz said the evidence shows Prince thought he was taking Vicodin, not fentanyl. He said there's no evidence any person associated with Prince knew he possessed any counterfeit pill containing fentanyl.
Prince was 57 when he was found alone and unresponsive in an elevator at his Paisley Park studio compound on April 21, 2016. His death sparked a national outpouring of grief, and prompted a joint investigation by Carver County and federal authorities.
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An autopsy found Prince died of an accidental overdose of fentanyl, a synthetic opioid 50 times more powerful than heroin. State and federal authorities have been investigating the source of the fentanyl for nearly two years, and have still not determined where the drug came from or how Prince got it.
While Carver County said it was ending its role in the case, the U.S. Attorney's Office had no immediate comment on the status of its investigation.
But a law enforcement official close to the investigation told The Associated Press that the federal investigation is now inactive unless new information comes forward. The official spoke on condition of anonymity because the case remains open.
Federal prosecutors and the U.S. Drug Enforcement Administration alleged Schulenberg, a family physician who saw Prince at least twice before he died, violated the Controlled Substances Act when he wrote a prescription in the name of someone else on April 14, 2016.
The settlement, dated Monday, does not name Prince or make any references to the Prince investigation. However, search warrants previously released say Schulenberg told authorities he prescribed oxycodone to Prince on April 14 and put it under the name of Prince's bodyguard and close friend, Kirk Johnson, "for Prince's privacy."
Schulenberg's attorney, Amy Conners, has disputed that and did so again on Thursday, saying that Schulenberg settled the case to avoid the expense and uncertain outcome of litigation.
Oxycodone, the generic name for the active ingredient in OxyContin, was not listed as a cause of Prince's death. But it is part of a family of painkillers driving the nation's overdose and addiction epidemic, according to the U.S. Centers for Disease Control and Prevention. Nearly 2 million Americans abused or were addicted to prescription opioids, including oxycodone, in 2014.
A laboratory report obtained by The Associated Press notes that one of the pills found in a prescription bottle in Paisley Park that bore Johnson's name tested positive for oxycodone.
"Doctors are trusted medical professionals and, in the midst of our opioid crisis, they must be part of the solution," U.S. Attorney Greg Brooker said in a statement Thursday.
The settlement notes that the agreement "is neither an admission of facts nor liability by Dr. Schulenberg." And in a separate letter to Schulenberg's attorneys, prosecutors say Schulenberg is not currently a target of any criminal investigation.
Under the settlement, Schulenberg also agreed to stricter requirements for logging and reporting his prescriptions of controlled substances for two years, and give the DEA access to inspect those records.
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It's illegal for a doctor to write a prescription for someone under another person's name. Anyone convicted of doing so could lose their DEA registration - meaning they could no longer prescribe controlled substances - and could face discipline from their state medical board.
The settlement says the DEA won't revoke Schulenberg's registration, unless he does not comply. It's unclear whether the state medical board will take action. His license is currently active and he has no disciplinary action against him.
A confidential toxicology report obtained by the AP in March showed high concentrations of fentanyl in the singer's blood, liver and stomach. The concentration of fentanyl in Prince's blood alone was 67.8 micrograms per liter, which outside experts called "exceedingly high."
Prince did not have a prescription for fentanyl. Search warrants unsealed about a year after he died showed that authorities searched his home, cellphone records of associates and his email accounts to try to determine how he got the drug. Authorities found numerous pills in various containers stashed around Prince's home, including some counterfeit pills that contained 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 performing at an intense level. Documents unsealed last 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.
Associates at Paisley Park told investigators that Prince was recently "going through withdrawals, which are believed to be the result of the abuse of prescription medication," according to an affidavit.
Just six days before he died, Prince passed out on a plane, and an emergency stop was made in Moline, Illinois. The musician had to be revived with two doses of a drug that reverses the effects of an opioid overdose.
The day before his death, Paisley Park staffers contacted California addiction specialist Dr. Howard Kornfeld as they were trying to get Prince help. Kornfeld sent his son, Andrew, to Minnesota that night, and the younger Kornfeld was among those who found Prince's body. Andrew Kornfeld was carrying buprenorphine, a medication that can be used to help treat opioid addiction.