MINNEAPOLIS — Prosecutors in the county where Prince was found dead have agreed to provide his siblings with investigative documents so the family can determine whether civil litigation is warranted, according to a stipulation filed in court Wednesday.

The siblings and their attorneys must keep the information confidential, or could be held in contempt of court, the agreement says. A judge hasn’t yet signed off on it, according to court records, but that’s typically a formality when both sides agree.

Prince was 57 when he was found alone and unresponsive in an elevator at his Paisley Park estate on April 21, 2016. An autopsy found he died of an accidental overdose of fentanyl, a synthetic opioid 50 times more powerful than heroin.

Search warrants released about a year later showed 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 around Prince’s home, including some counterfeit pills containing fentanyl. But the source of those drugs hasn’t been determined.