Final answer:
A lawful Terry stop allows police to temporarily detain and question an individual based on reasonable suspicion of criminal activity. However, the details given in the situation are insufficient to categorically determine legality without more context.
Step-by-step explanation:
The situation described presents a scenario where Officer Fief guides a person named Mark to an empty office for questioning shortly after his plane arrives. To determine whether this interaction could be considered a lawful Terry stop, one must reference the landmark case Terry v. Ohio. According to this precedent, police may stop an individual if they have reasonable suspicion that the person has committed, or is about to commit a crime. During such a stop, they can also conduct a frisk for weapons if there is reasonable suspicion that the person is armed and dangerous, without violating the Fourth Amendment. However, the brief description provided lacks specificity regarding the reason for the officer's suspicion and subsequent action. Additionally, the context of being led to an empty office may raise questions about the scope of the encounter. If the questioning extends beyond what is allowed during a Terry stop, such as being detained without probable cause or being denied one's rights, it may infringe upon constitutional safeguards.