It seems the movement of rubber stamp signatures for people with disabilities is growing.

Rather like company seals, automatic signature processes require tight security and integrity to reduce the potential of fraud, as a signature is a very personal mark of a person’s discretion.

A person’s regular signature is very personal. It is produced solely as a result of biological actions (brain controlling hand, for example).

Similar security with the use of a mechanical or electronic signature device will be quite difficult to achieve in practice. Nevertheless, a mechanical or electronic signature device may be the only way for those with just physical challenges to exercise their discretion,

In contrast, the concept of those intellectually challenged using a mechanical or electronic signature device would be very much dependent on their intellectual capacity to understand consequences and intentions. Similar to that needed to authorise an enduring power of attorney.

http://www.austlii.edu.au/au/journals/UNSWLJ/1998/56.html

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