Additionally, NTLD has not been tested with the type of individuals often encountered by law enforcement.
Finally, NTLD has not yet proven able to handle the shades of truth bound to exist in real-life situations.
Despite these limitations, NTLD research continues apace and, as described in more detail below, American courts are already confronting NTLD technologies and the questions they raise.
(52) Like fMRI, brain fingerprinting (and EEG-based NTLD in general) retains much promise but currently faces a host of limitations.
As with other types of NTLD, India has led the way in the judicial use of brain fingerprinting, employing it even against unwilling subjects as evidence of guilt.
BEOS (and NTLD more generally) received extensive press treatment after it was used in the case serving as the introduction to this Article.
(77) Jointly developed by the Mayo Clinic and Honeywell Laboratories, FTI differs from the types of NTLD previously discussed in that it does not attempt to measure activity within the brain directly, but instead measures the warming around a subject's eyes caused by "excessive blood flow to certain areas of the face." (78) This approach is premised on research indicating that "auditory startling is associated with a specific facial 'thermal signature'" and that individuals who are lying demonstrate similar warming patterns.
Having examined current and emerging NTLD technology, this Article now examines potential Constitutional limitations on its use.
(85) Technically, this means that law enforcement officers could illegally enter the homes of suspects and strap them into an NTLD for an examination without violating the Fourth or Fifth Amendments-as long as the evidence obtained is not used against them at trial.
For example, if a criminal defendant seeks to introduce NTLD evidence obtained from the defendant or a trial witness, questions regarding its use will be based on evidentiary and reliability concerns, not these constitutional provisions.
Thus, this Article ultimately focuses on a specific situation: law enforcement use of NTLD to examine an unwilling (93) person that results in evidence being used against that person in a criminal trial.
As a practical matter, this section primarily applies to fNIR and FTI technologies, as they are the only NTLD likely capable of being used without the subject's permission (that is, in-the-field use) in the foreseeable future.