From the written testimony:
Unfortunately, for years, IJs have been hobbled in performing their mission, largely as result of neglect of EOIR and of misguided immigration policies implemented by the Executive branch. Simply put, the immigration courts of the United States are failing at their primary mission of “adjudicat[ing] immigration cases by . . . expeditiously . . . interpreting and administering the Nation's immigration laws,” largely due to no fault of the IJs and staff who work in those courts.
The attorney general and his subordinates are actively working to remedy this problem, by providing the needed resources to the immigration courts, and by implementing bright-line rules for IJs and the BIA to follow in adjudicating the cases they consider. DOJ should be supported in those efforts by this committee and by the Congress as a whole.
Restructuring the immigration courts and the BIA will almost certainly fail to address the core problems that are facing those tribunals. Moreover, not only would such restructuring be complicated and costly (and likely ultimately ineffective), but any proposal that would move either the immigration courts or the BIA out of the executive branch would implicate serious constitutional concerns.