a plaster wall in a county hoosegow. one scratch is added each time you visit. book in with a charge and, if you like, a sentence length — the wall keeps a record of what you did time for. the wall is yours — nobody else's marks are on it.
Wipe the wall? Every scratch you've made will be forgotten. The count starts again from zero the next time you come in.
New stretch. State the charge, and the length of the sentence if it's known.
priors on file.