The administration has implemented a key strategy significantly to increase arrests, detention and deportation along unauthorized persons periods.  It will, in some, overcome one basic barrier, which is that while crossing the border in an unauthorized way is a misdemeanor, being in the country while they’re not authorized this is civil violation. Being a civil violation there is no authority to detain an individual, much less to impose a court judgment of a fine or jail time.

Alien Registration Act

One February 25, the administration issued a requirement that all aliens who a present in the United States without a visa register with the State Department. This is designed to make being in the U.S. a misdeameanor unless one registers.  (Go here.) And if one registers DHS can find them.

The registration for (AR-2) here which appears to be the one used asks for name at time of entry, other names used, date of first arrival, address, years lived in the United States, date of birth, citizenship/Nationality, usual occupation, fingerprint, gender, present occupation, and marital status. (Go here.)

The American Immigration Council summarizes the language in law:

8 U.S.C. section 1302, codified via the Alien Registration Act of 1940, requires all noncitizens over the age of 14 who have not already registered, and who are in the U.S. for more than 30 days, to register with the federal government within 30 days of their arrival. \

8 U.S.C. sections 1306(a) Under section 1306(a), any noncitizen who “willfully fails” to register with the government (or the parent of any noncitizen under 14 who fails to do so) after 30 days is guilty of a federal misdemeanor crime. If charged and convicted, it allows the noncitizen (or parent) to be sentenced to up to six months in jail and/or fined up to $1,000. Any adult who fails to carry proof of registration can be charged with a misdemeanor and fined up to $100.