[justinlardinois]

And they probably want something they could reliably continue to unlock the phone with. Sure, they could just remove all authentication once they're in, but maybe they want to tamper with the phone and its settings as little as possible.

[weaksauce]

I don't think you can make any changes to the security setting unless you know the passcode.

[justinlardinois]

Quite possibly. I don't think the article mentioned what kind of phone it is.