we have verbal warning as the first option at our place, i would expect her to be given that before jumping in to written.
I agree - although in most cases 'verbal' is a bit of a misnomer as you probably still receive written notice that a warning has been given , and it usually remains on file for 6 months - we have quite a prolonged process which goes
informal warning (no written notice given, nothing on file)
notification of poor performance (usually at PDR but can fall between times)
performance improvement plan (3 months to get your s*** together with support from the line manager)
formal verbal warning
1st written warning
final written warning
dismissal (although the hearing can chose other measures such as another warning , demotion , suspension, redeployment to a different post etc)
that said a disciplinary board can start at any step 'with good reason' - for example instances of gross misconduct would usually jump to final written or possibly straight to dismissal if warranted
The really key thing though (which ought to be common to most employers) is that any disciplinary should start with a thorough investigation of the facts - usually be the line manager, unless there are doubts about his impartiality, in which case another manager can be nominated to investigate. It is extremely unusual (and possibly improper) to jump straight to a disciplinary hearing without first having an investigative meeting/period to establish the facts.
(one point is that we've all been assuming the OP is in the UK - other countries employment laws vary dramatically , for example in America many states have an 'at will' policy - which basically means employees can be canned much more easily than they can on this side of the pond)