I suppose this makes sense — the property has been deemed "proceeds of crime," and it stands to reason that the sale of that property to mount a legal defence would be akin to using "proceeds of crime to defend that crime." I guess its no different than holding a suspect in custody during the trial, except its property.

Duggan is facing some serious charges and I imagine the seizure of the property, errors in the affidavit notwithstanding, is sensible.