Is someone who was tortured and then treacherously killed as a result of a conspiracy plotted against him considered a martyr?

Killing a soul whom Allah has forbidden to kill is a grave crime and a major sin. Its حرمة (sanctity/prohibition) increases if the killing is treacherous. Allah has threatened the intentional killer of a believer with Hell, eternal residence therein, His wrath, His curse, and a tremendous torment. As for being decreed a martyr, this depends on the existence of a Shar'i (legal) text. Some scholars are of the view that one who is killed unjustly is considered a martyr.