http://www.cnn.com/2005/LAW/11/04/inmate.escapes/index.html
Ermmm…maybe I’ve just lead a sheltered life, but…howdedodat? Unusually thin hands? Wrong size cuffs? Don’t they check to be sure the cuffs actually fit properly? Or can you just generally wriggle out of them if you have normal-sized hands and you’re patient and don’t mind a few scrapes?
With the key. They think that the guy had help on the inside.
One of the most common ways is for the handcuffs not being fitted properly.
The clasp must be closed above the ‘wrist’ bone, so they are actually on the lowest part of the forearm.
Most cons wearing them have no intention of escaping so even when badly fitted, there is no problem, naturally one only ever hears about these cases, but it is more commom than you might think.
I slipped out of handcuffs right in the police car (yes, I was arrested…). I was very thin at the time. I have a hard time understanding how an average size man would do it though.
(The cop asked me if I would kindly just “act” like the cuffs were still on when we walked into the station. I obliged him.)
You can get out of standard handcuffs with anything small such as a safety pin or a paperclip - if they’re not double locked. Years ago, I could do it in about 2 minutes, starting from having my hands behind my back. (with a paperclip) I haven’t tried it lately.
Which is why LEOs are trained to always do several things when handcuffing a subject: 1. Adjust and double-lock!!! Adjust and double-lock!!! Adjust and double-lock!!! Obviously, this point can not be overstated. Double-locking prevents the simple pick with a clothespin, as well as preventing the cuff from getting tighter on a subject. For adjusting, you should be able to just stick the tip of your pinky finger between the cuff and the wrist.
Some career criminal types, so I’ve been told in training, can doff a pair of handcuffs in an amazingly fast time. Sometimes they have lots of free time to plan these things. Idle hands and all that.
Actually double-locking is done mostly for the convict’s benefit - it prevents the handcuffs from tightening up further and cutting off circulation but it doesn’t really make them any more secure. The two main factors in ensuring the cuffs stay on is to make sure the original fit is right (which prevents them from being slid off) and putting them on with the lock on the inside (which makes it difficult for the wearer to reach the lock).
Sure it does. And in the interest of fighting ignorance, I just tried it. On a standard pair of Smith & Wesson chain link handcuffs, I double locked one side and left the other single locked. Using a safety pin, I opened the single lock side in a matter of seconds, and could not unlock the double-locked side. (not while actually hand-cuffed, mind you)
When in single lock mode, the key, or safety pin, only has to be turned from the 12 o’clock position back to about the 11 o’clock before the release mechanism starts to engage.
When double locked, the key has to be turned the other direction over 180 degrees to disable the double-lock. Much more difficult without a key. Not impossible I’m sure, but not nearly as easy as defeating the single lock.
Thanks for the input, all. 
In my experience most of the people who could easily get out of cuffs had small wrists and thin hands. Look at your hand and touch your thumb to your pinkie. On my hand the meaty part of the palm below the thumb is pretty thick and I could never get my hand through cuffs. If your hand was very thin this might narrow your hand enough to get it through the cuffs. I have seen this happen, usually with thin women.
I was in the back of a squad car with another gal who slipped her cuffs. I told to can it and put the fucking cuffs back on before she got me in trouble!
I always thought that this was to prevent someone from shimming the pawl away from the ratchet. This is one of the ways to open cuffs: slip something along the teeth of the ratchet, to lift the pawl and allow the ratchets to pass. If the cuffs are double locked, this attack fails since the pawl is locked in position.
Jeez, where are you guys being arrested? Mayberry?
About 7 years ago I was pulled over and handcuffed on suspicion of murder. They put the cuffs on very securely, and there was no chain: the cuffs were joined together by an armored hinge.
Because of the hinge’s restricted range of motion and the location of the keyhole, you could have handed me a shim, a lock-pick, or even the damn handcuff key and it wouldn’t have made a bit of difference to my freedom (or lack thereof).
Like I said, that was 7 or so years ago… I can only imagine what kind of technology real cops have to cuff real bad guys these days.