Court upholds manslaughter conviction; rules what you don't say to coworkers not the same as what you don't say to police

The Massachusetts Appeals Court today ruled Ivan Sosa gets to stay in prison for stabbing a co-worker to death in frustration over a woman they worked with.

Sosa, a cook at the Turner Fisheries restaurant, was convicted of involuntary manslaughter for the 2006 stabbing death of Carlos Borrero in the restaurant kitchen. The jury did not buy Sosa's argument he was forced to stab Borrero, a bartender, repeatedly in self-defense and instead agreed with prosecutors that Sosa just went berserk and kept plunging one of his work knives into Borrero.

Part of Sosa's appeal involved questioning from prosecutors on why, if Borrero had twice hit him in the head with a metal bowl after failing to pick up Sosa's knife, he hadn't said anything to co-workers immediately after the stabbing, even though he made other comments to them about the incident.

Sosa said this violated his Miranda rights to stay silent and that it could not be used against him. The appellate justices, however, disagreed, both because Miranda rights in a case like this only come into play after police have advised him of his right.

And in any case, the court continued, "the fatal problem with this argument, as recognized by the trial judge, is that the defendant did not remain silent after he received the Miranda warnings" - he did answer questions from an officer.

• Complete ruling.