Theresa May has insisted that Abu Qatada's arrest came after a three-month deadline for him to appeal against deportation to Jordan, despite the radical cleric's decision to mount a last-minute attempt to get the Grand Chamber of the European Court of Human Rights to intervene.
Qatada was arrested on Tuesday and has been appealing his deportation for 11 years, amid vetoes on his removal from Britain by the European Court of Human Rights.
The court has blocked his deportation on the grounds that his trial in Jordan on terror charges could rely on evidence obtained under torture.
The government now believes it has secured assurances from the Jordanian government that such evidence would not form part of a trial.
However Abu Qatada lodged a last-minute appeal to the Grand Chamber of the European Court on Tuesday night, potentially delaying his deportation by many more months.
In a blustery session in the Commons the home secretary claimed that the deadline for Qatada to appeal was midnight on Tuesday, and as such the decision to arrest him ahead of deportation on Tuesday was valid.
May told MPs: "Of course the government has been in contact with the European court during this period... It was always clear the government was working to a deadline of Monday."
However May made the surprising revelation that the Grand Chamber of the European Court could, if they chose to, allow an appeal even if it was made after the deadline.
But she insisted that the government had followed guidance from the European Court, and that she was "absolutely clear" the deadline for an appeal had passed on Monday night.
However because the European Court as no automatic process of rejecting appeals, it would be considered. "A rule 39 injunction remains in place," May said. "The process is put on hold until as soon as the injunction is lifted," she added, reminding MPs that Abu Qatada remained in detention and that the Home Office would continue to build the case for deporting him.
The Rule 39 injunction is an impostition by the European Court which will delay domestic attempts to deport Qatada. It is one of the processes which Britain is leading on attempts to reform, because the UK government believes its processes lead to lengthy delays.
Britain currently holds the presidency of the European Council and is seeking to use its brief period of leadership to end lengthy backlogs of cases within the court, which currently reviews cases in the order on which it receives them. Britain would like to introduce automatic rejections of claims to the court which are obviously spurious.
Shadow home secretary Yvette Cooper lambasted May for "partying with X factor judges" on Tuesday night, whilst Qatada was in the process of appealing.
"Several eminent lawyers are now saying Abu Qatada has a case," Cooper told MPs. "Why take the risk? Why not wait until Wednesday?" she asked May.
Various MPs stood up during the subsequent debate - with some Tories calling on the government to withdraw Britain from the auspices of the European Court. Others urged ministers to be more forceful in getting the European Court reformed - a process underway at a high-level conference of the European Council in Brighton taking place this week.