On immigration, Attorney General Barr is his own Supreme Court. Judges and lawyers say that’s a problem.

Attorney General William P. Barr quietly intervened in an immigration asylum case last week when he issued a decision that narrowed the definition of torture for asylum seekers who invoke it as a grounds for staying in the United States.

Barr used a process known as “certification,” a historically little-used power of the attorney general that allows him to overrule decisions made by the Board of Immigration Appeals and set binding precedent. Immigration lawyers and judges say the Trump administration is using the power with greater frequency — to the point of abuse — as it seeks to severely limit the number of immigrants who can remain in the United States. The administration is also using it as a check on immigration judges whose decisions don’t align with the administration’s immigration agenda, experts say.