Good grief. You're going to argue based on technicalities? Okay orcs all have "antisocial personality disorder". Heaven forbid I use the common real world vernacular and not the definition according to the Diagnostic and Statistical Manual of Mental Disorders.That's not a scientific fact dude, that's a political opinion that science has failed to validate. Sociopath isn't even a scientific term. Look it up if you don't believe me. I'd link wikipedia but it's not a real term so it's not there.
Point is, some people effectively don't have what we would consider a "conscience". I see no issue with a fictional species like orcs lacking a conscience as we define it.