On Tuesday, a New York-based school librarian named Jennifer Iacopelli put on her detective cap after a crying student approached her for help.

According to a series of increasingly Sherlock-esque tweets, she is apparently a master of both the Dewey Decimal System and sleuthing.

Victory of the day, settle in folks: Student comes to the library this morning in tears. She's grounded. Her mom took away her phone. — Jennifer Iacopelli (@jennifercarolyn) January 31, 2017

The story, as told to Twitter, goes: When Iacopelli asked why the crying student was grounded, she claimed that someone had “hacked” her English paper, adding “inappropriate things” to the assignment, which her mother believed she had written.

She says that someone "hacked" her English paper and wrote very inappropriate things in it. When she and her mom sat down to work on it last — Jennifer Iacopelli (@jennifercarolyn) January 31, 2017

night, her mom saw it and FREAKED on her (rightly so IMO). The student is 12 and if my 12yo had written this it would have been DEATH. — Jennifer Iacopelli (@jennifercarolyn) January 31, 2017

The student insisted that the inappropriate additions to her paper, which she’d been working on using Google Docs, were not her own. Intrigued by the alleged hacking, Iacopelli went on the hunt to figure out how the paper ended up in this condition.

However, student INSISTS that she didn't write it. So I go into her Google Doc account and see that the changes were made at 2:16pm. — Jennifer Iacopelli (@jennifercarolyn) January 31, 2017

Student says, "I was on the bus then!" So I pull up the camera security footage we have in the library computer lab for 2:16pm. — Jennifer Iacopelli (@jennifercarolyn) January 31, 2017

There are three boys sitting around a computer, two hovered over another who is typing. I rewind the footage and see Student! — Jennifer Iacopelli (@jennifercarolyn) January 31, 2017

She turns away from her desk at the end of the previous period, monitor times out, she gets up and walks away. 5 minutes later boys sit down — Jennifer Iacopelli (@jennifercarolyn) January 31, 2017

After parsing through edits on Google Docs and diving into library security footage, Iacopelli realized that the student had used a library computer to work on the paper ― and that the computer she used earlier in the afternoon was used by three boys after her.

The security footage showed that the boys had tampered with the paper after the student likely left Google Docs open.

One nudges the mouse and the screen lights up, still on Student's Google doc, which they hover over a for a good 15 minutes typing. — Jennifer Iacopelli (@jennifercarolyn) January 31, 2017

After showing the footage to another library aide, Iacopelli realized they could track the boys down.

I wait the footage out, see them turn around a few times and screenshot it. Ask one of the library aides. She knows one of them! — Jennifer Iacopelli (@jennifercarolyn) January 31, 2017

Then I check my sign-in records for the period! Three boys about the same age signed in together. Look up their student records and SHOCK! — Jennifer Iacopelli (@jennifercarolyn) January 31, 2017

Actually not shock, because BAM their pictures match the kids in the surveillance footage. All 3 written up, in school suspension. — Jennifer Iacopelli (@jennifercarolyn) January 31, 2017

Long story short, all three boys were punished for their paper sabotage, all thanks to the librarian’s expert investigative work.

But that wasn’t the only good news:

Student's grounding has been lifted and Mom said that she'll be returning her phone to her when she gets home today! — Jennifer Iacopelli (@jennifercarolyn) January 31, 2017

Clearly, Iacopelli is a badass.

Lesson: your friendly librarian is better at technology than you, so don't pull crap like that. I will find you and you will pay. pic.twitter.com/J99GojtgIS — Jennifer Iacopelli (@jennifercarolyn) January 31, 2017

And Twitter seems to love this solved mystery.

@jennifercarolyn This is like an episode of Veronica Mars. Well done. 🔍👏 — Anna Kovatcheva (@warblebee) February 1, 2017

@jennifercarolyn Awesome detective work! Also, I'd HOPE I knew my kid well enough to know if they'd write something like that. — 🖤❤️Sarah Blair❤️🖤 (@SarahLBlair) January 31, 2017

Never underestimate a librarian, friends.



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