Muggles' Guide to Harry Potter/Magic/Probity Probe

Muggles' Guide to Harry Potter - Magic
Probity Probe
Type	Magical device
Features	Detects concealment and deceit
First Appearance	Harry Potter and the Half-Blood Prince

Overview

Probity Probes are long, silvery probes that allow the bearer to detect concealment and deception: for instance, a Probity Probe would detect use of Polyjuice Potion to disguise oneself, and presumably would detect someone under an Invisibility Cloak.

Extended Description

We first hear of Probity Probes when Harry is preparing for his sixth year at Hogwarts. Bill, who works at Gringotts, hands Harry a money bag, saying that he's gotten some cash for Harry; everyone going into Gringotts now has to pass people with Probity Probes, and entrance to the bank can take several hours.

When Harry, Hermione, Ron, and Griphook enter Gringotts in Harry Potter and the Deathly Hallows to open Bellatrix' vault, there are two wizards with Probity Probes by the door. Harry, from under his Invisibility Cloak, Confunds them so they will not scan Hermione, who is in disguise.

Analysis

The principles behind a Probity Probe, a Secrecy Sensor, and the part of the Marauder's Map that determines the name of an individual, must be related, however their operation is clearly somewhat different.