Logan says it shouldn't be overly difficult to find out if any Russians bought the kind of shotgun shells used in the murder because they would need to show a gun permit to buy ammo. However at the time this episode takes place the only ammo that required a permit to purchase was handgun ammo, a permit was not required to own a rifle or shotgun or to buy ammo for one.
When the detectives first see the male victim's body there is tape on the floor in the usual 'body outline' manner. Unfortunately the blood from the body is on top of the tape instead of under it.
The crime lab says there are two distinct sets of fingerprints on the shotgun that killed the couple, the husband's and the younger son's. However, Det. Profaci handled the gun in the opening scene, and his prints should be on the stock and the slide rack. No mention is made of a third set of prints.
The supposedly Russian Osinskis speak Russian with non-Russian accents and mispronunciations.
The detective at the murder scene shows Logan and Greevey a shotgun that has been fired, but he's not wearing any gloves or handling the weapon in such a way as to preserve any fingerprints.