What is a necessary step when an agent suspects an individual is a non-U.S. citizen?

When an agent suspects that an individual is a non-U.S. citizen, utilizing all DHS data systems to confirm that individual's status is essential. These data systems contain comprehensive and up-to-date information that can verify an individual's citizenship status, immigration history, and any associated legal matters. This step helps ensure that the agent operates based on accurate and authoritative data, which is crucial for adherence to laws and regulations regarding immigration enforcement.

Using these systems not only streamlines the identification process but also provides necessary support for any subsequent actions that might need to be taken, whether that involves arrest, detention, or referral to immigration authorities. The other options may not provide directly relevant information or could compromise the integrity of the investigation, emphasizing the necessity for using data systems as a reliable source for confirming citizenship status.