What does a security guard need to do before conducting a search of a person?

A security guard must obtain consent or have probable cause before conducting a search of a person because this ensures that the search is legally justified and respects the individual's rights. Consent involves the person's voluntary agreement to be searched, which is a fundamental principle of respecting personal privacy and autonomy. If consent cannot be obtained, probable cause, which is a reasonable belief that the person may be involved in illegal activity, can also provide a legal basis for conducting a search. This is vital in order to avoid legal repercussions for conducting an unlawful search or violating a person's Fourth Amendment rights against unreasonable searches and seizures.

The other options do not align with the necessary legal framework governing searches. For instance, notifying law enforcement may be appropriate in certain situations, but it does not directly empower a security guard to conduct a search without prior consent or probable cause. Searching someone immediately ignores the legal and procedural steps that need to be in place to ensure the search is conducted lawfully. Additionally, checking someone's background history, while potentially informative, does not provide the immediate legal justification required for a physical search of a person at that moment.