The US government, under court order to quickly reunify parents and children who were separated after crossing illegally into the United States from Mexico, has expanded its use of DNA tests to establish paternity in immigration matters.
The government says DNA testing is a faster means of confirming parentage than relying on assembling documents such as birth certificates.
Under President Barack Obama, DNA testing of unauthorized border-crossers was rare, former administration officials said, but one said it was sometimes used as a last resort to verify family connections when placing unaccompanied minors with sponsors in the United States.
It was also used, and still is, to verify family ties of many refugees seeking permission for family members to join them in the United States.
Such testing looks at a small portion of DNA, known as “short tandem repeats,” to identify inherited regions of DNA that can vary from person to person.