I don't have all the details. The execution procedure did not begin at 6:00 PM local as was scheduled. It is now 7:05 local and it seems as if the procedure has not yet started. Feedback from the scene is that the execution has been "gummed up" by all the motions that have been filed. Since all the state motions have been ruled on, that would leave the two civil suits that have not yet been ruled on.
The civil suits are against the City of Houston and the Texas Board of Paroles and Pardons. Each has a different basis, which I'll not detail here. Basically, however, the separate suits are separate claims at the federal district court level that the two government entities have violated and continue to violate Mr. Hughes' constitutional rights to due process and to be free from cruel and unusual punishment.
I do not know whether or not those suits must be ruled upon in some fashion before the execution proceeds, but something is gumming up the works. The law is that a person must be executed by midnight on the day of their execution. My understanding is that the prison refuses to begin an execution after 11 PM so that they can stay in compliance with their legal mandate. My understanding is also that the death warrant is good for one day only. While a new death warrant could be quickly issued, it must put the execution date at least 30 days out.
Take every single thing I say here with a grain of salt. I'm speaking from zero experience and with almost no insight into what is actually going on.