Toonby, who usually works as personal assistant to the charity's director general Bryan Dutton, had donned an extravagant Scarlett O'Hara costume evoking the Leonard Cheshire red feather logo for an office cake sale that she had organised to raise money.
However, before she could get stuck into the cakes and scones, she was 'arrested' by two Metropolitan Police officers for "being in possession of and wearing a ridiculous outfit to the annoyance of residents and the public at large".
She was held in custody while an email was sent round the Leonard Cheshire office seeking sufficient 'bail' for her release. The stunt, arranged by the Leonard Cheshire Week central office committee with the help of Belgravia police station, raised £320 - more than double the minimum £150 set by the arresting officers.
Toonby's brush with the law was just one of a package of activities run for the charity's second annual Leonard Cheshire Week, which ran from 4-11 October. About 120 of the charity's 150 service centres that provide support to disabled people arranged their own fundraising activities in addition to a number of national events.
Thrill-seeking supporters took part in a sky-diving weekend, and there was a national raffle, costumed street collections and limited edition Looney Tunes badges. The charity also encouraged supporters to organise their own events. The total amount raised won't be known for some weeks.
"Leonard Cheshire Week has been a great success in terms of involvement from our service users, staff and volunteers across the country," said the charity's head of events, Sharon West.