smile you're on library camera

a woman came into the library yesterday with a print out of her account. it turns out she has three very overdue books on her card. she tells me that she returned these books back in january, before the due date. we get this all the time and there are only two ways it can play out:
Scenario A: this woman legitimately returned her items in our self-check-in machine (high tech machine that sucks books into a book drop whilst simultaneously scanning them in), but for whatever reason there was an error with the machine (happens often) and the items were not checked in. these items would then be found on the shelf.
Scenario B: this woman never checked these items in. either she is mis-remembering returning these items (like the time i thought i returned the VH1 best of the 80s CD but instead i found in wedged under the seat of my car 3 months later) OR she is flat out lying to me.
now, i never know which scenario i am dealing with but i like to give people the benefit of the doubt and assume that they did in fact return their items. that is, until i can prove otherwise. because as i have proven time and again, i am no sucker.
so we go to the shelf to look for the books and lo and behold ALL THREE are nowhere to be found. this is what we call in the biz, a clue. i mean, it is totally reasonable that one book could wind up not getting checked in and one book could be misplaced. but THREE books not getting checked in and THREE books all being misplaced. that is a stretch. sometimes the most obvious conclusion is the right one. the obvious conclusion here being that this woman never returned her books and that we are dealing with Scenario B.
but this woman is sticking to her story that she returned the books. i tell her that she should scour her home for the books and make sure they are not there. she looks at me in complete disgust and says that nothing could ever be lost in her home. her home is immaculate and the idea of something being misplaced there is absurd. i assure her that there is nothing to be embarrassed about if your library books fall behind the couch or wind up hidden under the bed. this happens to the best of us. but she is not budging. i reiterate that since it is THREE books, and since unfortunately i see no evidence that the books were returned, i can only assume that she never returned the books.
and this is where it gets good ....
"well i returned something here!" she says. "i even got a receipt, but then i threw it out."
this is always the case. the check-in machine gives receipts, but does anyone keep their receipt? no. i mean, at least check to make sure your account is clear and then throw away the receipt. i mention this to her but she is unmoved.
"then what did i return?!"
"well, i don't know" i say, "once you return books they are off your card." (we do this so the government can't spy on you. no need to thank us. it's just what we do.)
"don't you have cameras here?" she asks, then points to the dome cameras on the ceiling. "there's your proof. just look through the film."
at this point i am working very hard not to laugh in this woman's face. first, i have no idea if those cameras are actually filming anything. that's a lot of film, no? second, i have no idea who actually has access to that film and where that film is kept. i always assumed that the camera recordings would only be used 1. if something sizeable was stolen, like one of our computers OR 2. if there was a serious incident of violence. i cannot imagine that the cameras are there to see if this woman really returned three children's books.
"ma'am," i say, "this is the library. we're not james bond. we can't go through the past four months of camera recordings and find you and then zoom into a close up to see what books you are returning."
realizing that i won't budge, she finally asks me what she can do. i tell her that it is my recommendation that she go home and thoroughly search her house. then she walks off muttering about how clean her house is and she returned these books and oh, the injustice of it all.
i hope i am here to witness when she returns days, weeks, or months later having found the books under the seat of her car.