What could be a method used to pass contraband through a checkpoint?

The method identified as a way to pass contraband through a checkpoint is the concept of "Pass Throughs." This term generally refers to the act of getting items, particularly illegal goods like contraband, across a security checkpoint without detection.

In the realm of law enforcement and security, contraband can be smuggled in various ingenious ways, often exploiting vulnerabilities in security protocols or utilizing distraction techniques. Understanding the behaviors and methodologies used by individuals attempting to smuggle items can help agents develop more effective monitoring systems and responses.

Other methods, while relevant in the context of law enforcement, do not specifically pertain to passing contraband through a checkpoint. For instance, direct investigation is focused more on gathering evidence or assessing a situation rather than a method of smuggling per se. Controlled purchases may refer to operations where agents buy illegal goods to gather intelligence, while wiretapping is generally used for intercepting communications rather than physically moving contraband. Therefore, "Pass Throughs" stands out as the most applicable method in this context.