The problem of line-ups as forced-choice tests is one that Gary Wells and
others have researched extensively.  Gary has some great data showing the
false positive rates in the simultaneous lineup with an implied (or overt)
"pick one" task versus sequential lineups, in which an unspecified number of
potential choices are presented one at a time, with a "yes/no" response
given immediately after each "suspect."  Others have looked at "none of the
above" as a response option in the simultaneous lineup, two simultaneous
lineups (perpetrator present/ perpetrator absent) in which the first choice
is to select which lineup includes the perpetrator and then select one
person from that lineup, and other procedures to minimize false
positives.  In real police investigations there is a strong implication that
the witness would not have been called in for a lineup ID unless the police
believed they had their hands on the perpetrator, so giving "none of the
above" as a potential response isn't as strong a deterrent to false
positives as one would hope.  Realistically, the second procedure can only
be used in research.  In a real investigation, police don't know who the
perpetrator is and could easily create two perpetrator-absent lineups,
although some false positives can be readily identified if the witness first
selects the lineup constructed only from foils.  In real lineups,
identifying false positives sometimes happens anyway because some of the
foils may be staff at the station, off-duty officers, etc., who are known to
not be the perpetrator.  Sequential lineups are so good at reducing the rate
of false positives (but don't eliminate them), that the Department of
Justice and police groups in the UK have been advocating adopting these
practices.

The line-up procedure itself would be an interesting research topic for your
student, although it would largely be a replication of existing work.
Claudia Stanny

---
You are currently subscribed to tips as: [email protected].
To unsubscribe click here: 
http://fsulist.frostburg.edu/u?id=13090.68da6e6e5325aa33287ff385b70df5d5&n=T&l=tips&o=5066
or send a blank email to 
leave-5066-13090.68da6e6e5325aa33287ff385b70df...@fsulist.frostburg.edu

Reply via email to