In the recently argued Nielsen v. Preap case, the High Court was asked to weigh in on whether the federal government waived their right to detain individuals for removal proceedings after being released from state custody if the individual was not detained immediately, or within a reasonable amount of time.
Unfortunately for the Court, and a likely reason as to how the case even landed there, the parties seemed hung up what Congress meant in using the word "when" in the statute. Essentially, the statute in question requires the feds to detain certain individuals "when the alien is released." And like the debates over the word "is" from the 90s, this arguments seemed equally unimpressive.
Ambiguity of Injustice
As the federal government's attorney pushed at the oral argument, the meaning of "when" is unambiguous in terms of conferring a right for the feds to detain an individual, pretty-much, whenever. Meanwhile, the challengers argued that the meaning of "when" in context means immediately or within a reasonable period of time, such as 24 hours.
Justice Breyer seemed to indicate support for the challengers when he asked the government's attorney whether the government could wait 50 years to detain someone on that statute. Justice Breyer further expressed that a statute that allowed such would have serious constitutional problems. But more conservative justices Alito and Thomas are not expected to share these sentiments.
However, rookie Justice Brett Kavanaugh seemed inclined against reading the word "when" to impose a time limit when congress itself didn't specifically impose one.