Just for the record the webpage for the US Embassy in Reykjavik carries the following information for visitors.......

'Since its launch in January, the US-VISIT program has helped DHS and DOS officials intercept more than 200 persons with prior or suspected criminal or immigration violations. These included convicted rapists, drug traffickers, individuals convicted of credit card fraud, a convicted armed robber and numerous immigration violators and individuals attempting visa fraud.

Experience has shown that the US-VISIT enrollment process is fast and easy for travelers and works as an added layer of security. Since deploying US-VISIT entry capabilities at 115 airports and 14 seaports on January 5, 2004, more than 2.5 million foreign nationals have been processed without adversely impacting wait times.

Currently, US-VISIT requires that most foreign visitors traveling to the U.S. on a visa and arriving at an air or sea port have their two index fingers scanned and a digital photograph taken to verify their identity at the port of entry. By September 30, 2004, this process will also apply to visitors traveling under the VWP at all air and seaports of entry.'

Obviously anyone with a previous violation of immigration regulations, such as knowingly overstaying a Visa, will fall into this category and risks being included with the 'standard practice' that deals with all categories including drug traffickers etc. if attempting re entry into the country.

I'm not condoning the treatment this woman received but the Embassy advice to travellers makes the situation fairly clear.