Northway, 31, Richmond, died on Sept. 4, of asphyxiation caused by external compression, according to the Ramsey County Medical Examiner's report.
Northway and his brother, Bryan, fought with bar patrons at Doochies Bad Company Bar in St. Martin, according to the sheriff's department.
The case stalled in December as the Stearns County District Attorney's office waited for reports from the Minnesota State Highway Patrol. Those reports came through in late February, said Mary Yunkers, head of the criminal division for the county attorney.
Bryan Northway received a subpoena Monday requesting him to testify, according to the St. Cloud Times.
After hearing evidence in the case, the grand jury could decide on charges, including murder charges.
Grand jury proceedings are confidential.