Lockpicking: What It Is, Its History, and Its Place in Security

What "Picking" Means

The Lock Industry Standards and Training (LIST) Council's Professional Locksmith Dictionary defines the verb "pick" as "to manipulate tumblers in a keyed lock mechanism through the keyway, without obvious damage, by means other than the specifically designed key." ANSI/BHMA A156.30, the American standard for high-security cylinders, uses nearly the same wording in its own definition of picking.

Two neighboring terms are easy to confuse:

• Manipulation. In the LIST dictionary, "manipulation" is an opening method for mechanical combination locks, one that uses the lock's tolerances to find an opening combination. It is the combination-lock counterpart to picking a keyed lock.
• Decoding and impressioning. Picking aims to operate the lock. Decoding aims to learn the key combination, and impressioning fits a working key to the lock. A156.30 tests resistance to decoding separately from resistance to picking.

Why Picking Is Possible in Principle

No mass-produced lock is made to exact dimensions. Locksmith Ledger's overview of the subject explains that locks are manufactured within a set of tolerances, plus-and-minus limits on machined parts and on the materials themselves, because making every part identical would make locks impractically expensive. Tiny differences between parts are the reason a keyed mechanism can, in principle, be worked without its key. The same article notes that locksmiths pick locks because picking is a non-destructive way to provide access when no key is available, after which the lock can be serviced or rekeyed.

That is as far as this article goes on mechanism. For how the parts themselves work, see pin tumbler locks.

History: Challenges, Detectors, and the Great Exhibition

Security against picking drove much of early modern lock design. In 1778 Robert Barron patented a double-acting lever tumbler lock (British patent No. 1200), in which each lever had to be lifted to a precise height before the bolt could move. Sources differ on the exact date of the patent. The Lock Collectors Association gives February 27, 1778. George Price's 1856 Treatise and a collector's history give October 31, 1778, and Price notes that many earlier writers put the patent in 1774. See Robert Barron.

Joseph Bramah's firm displayed a padlock in its London shop window with an offer of 200 guineas to anyone who could open it without the key. In 1818 Jeremiah Chubb introduced his detector lock, which, as the Linda Hall Library describes it, froze up if tampered with so that the owner would know someone had tried to pick it.

Both claims of security were tested at the Great Exhibition of 1851. Alfred Charles Hobbs, an American locksmith representing Day & Newell of New York, took up the Bramah challenge under agreed conditions: he worked on the firm's premises and the lock had to remain undamaged and working. According to the Linda Hall Library, he opened it after 51 hours of work over 16 days, using specially made instruments, and was paid. He then opened a Chubb detector lock. The Science Museum Group, which holds the Bramah challenge lock, credits Hobbs as the first person to pick it. The Linda Hall account adds that Bramah and Chubb sales do not appear to have suffered, and that Day & Newell's own parautoptic lock was later picked by Linus Yale.

Hobbs defended open discussion of lock weaknesses. In his 1853 book Locks and Safes, quoted by The Open Organisation Of Lockpickers (TOOOL) in the United States, he wrote that "Rogues knew a good deal about lock-picking long before locksmiths discussed it," and that the spread of that knowledge "is necessary to give fair play to those who might suffer by ignorance." For a fuller timeline, see Alfred Hobbs and Joseph Bramah.

Locksport and Ethics

Hobbyist picking is organized through locksport clubs, and their rules are strict. TOOOL Netherlands says the most important rule for its members is "to only open locks that you have permission for to open from the owner." Its members avoid discussing opening doors or stealing bicycles, and the board acts if such topics come up.

The same club corrects a common belief that picking leaves no trace: "The tools make scratches in the lock in places a key would never come into contact with." It reports that SSDeV, the German locksport association, opened test locks for the German federal forensic laboratory, which could then tell what technique had been used and roughly how many times. That is the basis of forensic locksmithing. For clubs, competitions, and disclosure debates, see locksport.

Legal Context

Laws on lock picks differ by country and, in the United States, by state. Three documented examples show the range:

• Netherlands. TOOOL Netherlands states that lockpicking is legal there and that anyone may own a pick set.
• Virginia. Code of Virginia § 18.2-94 makes possessing "any tools, implements or outfit, with intent to commit burglary, robbery or larceny" a Class 5 felony, and says possession by anyone other than a licensed dealer is prima facie evidence of that intent.
• Nevada. NRS 205.080 makes possessing a "picklock" or similar implement a gross misdemeanor when circumstances show intent to use it in a crime. Possession outside a tradesperson's established place of business is prima facie evidence of that intent.

These are examples, not a survey, and this article gives no legal advice. Check the law where you live. Opening a lock you do not own or have permission to open is a separate matter from owning tools.

How Standards Account for Picking

Lab standards treat picking as one attack among several and measure resistance to it under controlled conditions.

• UL 437 (Key Locks). Published summaries of the standard, including a 2007 DEF CON presentation by Marc Weber Tobias and Matt Fiddler, list picking as a timed covert-entry test alongside impressioning, with forced-entry tests such as drilling and prying. See UL 437.
• ANSI/BHMA A156.30 (High Security Cylinders). The 2014 edition defines pick-resistance requirements in levels. They include design features such as detainers "that have false notches, mushroom shapes or other constructions that impede manual picking," reference UL 437's pick-resistance paragraph, and at one level require a timed picking test by five ALOA-registered locksmiths with at least five years of experience. Pin and Ward is not stating which A156.30 letter level is highest until the current edition's text is checked.
• ANSI/BHMA A156.5 (Auxiliary Locks). The 2014 edition advises that "where pick resistance and other higher security protections are required," specifiers consider locks meeting UL 437 or A156.30.

A156.30 itself cautions that its tests are performed under laboratory conditions and that results in actual use may differ. A rating describes the result of a defined test, not a guarantee. See high-security locks, security pins, and sidebar locks.

Related Topics

• Locksport
• Pin tumbler locks
• Impressioning
• Decoding
• Key bumping
• High-security locks
• UL 437

Sources