Roper's bail has been set at $50k ... and prosecutors expect him to surrender.
As we previously reported, Morgan was riding in a limo bus on the NJ Turnpike on his way home from a gig last night ... when it was rear-ended by an 18-wheeler and overturned.
Tracy and another passenger were airlifted to a nearby hospital where they remain in critical condition. Another passenger, James McNair, was pronounced dead at the scene.
According to reports ... Morgan's opening act Ardie Fuqua -- who posted a photo of Tracy roughly 30 minutes before the accident -- is also in critical condition.
Prosecutors say the cause of the 6-vehicle wreck is still under investigation.