Stephen "Stevie" Walter was arrested Monday in Los Angeles on a charge of conspiracy to distribute a controlled substance, TMZ reported.
Miller died Sept. 7, 2018, at the age of 26 in an apparent drug overdose, according to media reports from the time.
Cameron James Pettit, Miller's alleged drug dealer, who was arrested earlier this month, contacted Walter the night of Sept. 4, 2018, asking for Percocet pills, media outlets reported, citing court documents.
Police said Walter then had a runner deliver the pills to Pettit, who delivered them to Miller on Sept. 5, according to court documents.
The alleged runner, 36-year-old Ryan Reavis, was arrested Wednesday.
Walter is currently on supervised release following a 10-year federal drug trafficking sentence, TMZ reported. He remains in custody.