have you read the article? it gives an example of a murderer who tried to fool metrocard ... but failed
the metrocard itself cannot be used to identify a person's whereabout; however, it can be used to constrain the movement
the key word in that article is "physically" ... the metrocard data is used to determine how physically plausible an action is
for example, one uses metrocard at 9amET in new york, then someone get killed in LA at 10amET, s/he can't be physically possible candidate even if ALL govt witness say so
of course, orthogonal info help too, a phone call at 930amET or even 705amET ATM withdrawal (with pic)
the metrocard itself cannot be used to identify a person's whereabout; however, it can be used to constrain the movement
the key word in that article is "physically" ... the metrocard data is used to determine how physically plausible an action is
for example, one uses metrocard at 9amET in new york, then someone get killed in LA at 10amET, s/he can't be physically possible candidate even if ALL govt witness say so
of course, orthogonal info help too, a phone call at 930amET or even 705amET ATM withdrawal (with pic)