Via Syracuse University's TRAC Immigration:

According to the case-by-case court records analyzed by the Transactional Records Access Clearinghouse (TRAC) at Syracuse University, during March 2017 there were 318 new federal civil filings involving these immigration matters. This number is up 5.6 percent over the previous month when the number of civil filings of this type totaled 301. See Table 1.

When monthly 2017 civil immigration filings are compared with those of the same period in the previous year, their number was up 40.5 percent. Civil filings for March 2017 are higher than they were for the same period five years ago. Overall, the data show that civil filings of this type are up 105.6 percent from levels reported in March 2012.

TRAC also determined that:

Nearly half (47%) of the 763 suits filed since January 20, 2017 were brought by individuals detained by Immigration and Customs Enforcement (ICE). These individuals sought release from their detention and/or a court order to prevent their deportation. Most of the remaining suits challenged government inaction. One third (33%) were mandamus suits to compel the federal government to act on visa or related applications. Another 8 percent sought a hearing or other action on naturalization applications.

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