"We believe the revocations were improper," Mr. Horn said.
Fines or license revocations are rarely used to enforce safety rules.
But investigations are time consuming and only a dozen or so result in revocations each year.
The parole revocations themselves, in California, can last from a few weeks to a year.
However, there would be a post facto judicial review of revocations that fall in that category.
"Taxi crackdowns" by the police, license suspensions and revocations all take their toll.
Then came last week's revocations, which erupted into a global controversy.
Thursday's revocations came a day after Pennsylvania's Lehigh University rescinded an honorary degree given in 2005.
"We've known for a long time that these things were problematic, and the high number of revocations is further proof".
Abbott suggested the revocations would not necessarily affect all groups proscribed as terrorist organisations under Australian law.
The majority of Ofcom's previous licence revocations have been in relation to what one might call "babe channels".
