In Bristol there have been a series of dwelling burglaries, whereby the properties are being attacked due to the nature of their exterior door handle - a paddle / stub exterior door handle.
The design is that once the door is shut you cannot open the door again from the outside using the paddle / stub handle on the exterior.
Victims they believe that once the door is closed that means their door is locked and their home is secure. This is not the case. These doors are still easily opened and this is why burglars are specifically targeting homes with these handles.
The 2 methods of entry of burglars are as follows:
1) They put their hand in through the letterbox and use a stick or pole to knock down the interior door handle, which then opens the door. If the door was locked using the key, and the key is still in the door, some offenders hook the key out of the lock and use it to unlock the door from the outside.
2) They place a small screwdriver / bradawl in at lock height which disengages the releaser of the lock, which then makes the exterior handle work and the door can be opened. This style leaves very little visible damage to the door, and can only be seen upon very close inspection.
If the victims used their keys to lock the doors and took the keys out of the lock, then offenders could not break in using the above methods.
Victims also believe that by lifting the interior door handle that means the door is locked. Again this is not the case, it purely engages the lever hooks into the frame, but once the offender disengages the releaser in the lock using a tool, this allows the offender to open the door using the exterior door handle as the mortice lock has not been locked using the door key.