What makes a person agree to a police search without a warrant, despite being legally allowed to say no?

Vanessa Bohns, associate professor of organizational behavior in the ILR School, will measure whether perception causes outside observers to systematically overestimate the voluntariness of consent – information particularly relevant in court cases on issues such as immigration. The work has received $250,855 in National Science Foundation funding.

Results are expected to provide the legal community and the public with data and recommendations that could have impact in courtrooms and on policy affecting policing tactics, police-community relations and digital privacy, Bohns said.

“With the current focus on the efficacy and fairness of policing tactics, there is now a genuine opportunity to assess how government agents seek consent from citizens. Ultimately, the development of policies backed by empirical research on the psychology of consent will lead to more just outcomes for citizens subjected to consent search,” Bohns said.

Bohns further explained how consent issues can play out: “If someone was searched by the police and then argued that they did not voluntarily consent to be searched, their case would be decided by a judge who would need to determine whether their consent was truly ‘voluntary.’ We think such determinations are systematically biased because outsiders view consent as more voluntary than it is experienced by the person confronted with the prospect of saying ‘no’ to a police officer.”

Consider the increasing number of people being asked for documents related to immigration. When law enforcement agents ask for documents without probable cause, in which case people don’t have to hand anything over, they often feel compelled to comply, she said.

In three studies conducted over two years by Bohns and her collaborator, Roseanna Sommers of the University of Chicago, people will be asked to unlock their password-protected phones or hand over their bags to be searched, or to imagine what it would feel like to be asked to hand over these items and what they would do.

“We hypothesize that people who simply imagine what it would be like to be asked to hand over these items will believe it would be relatively easy to say ‘no’ to such requests, but in fact those who are asked will find it incredibly difficult to say ‘no,’ she said.

Most police searches are authorized by voluntary consent. Consent searches do not require probable cause, which means that an individual can be singled out based on an officer’s hunch or for no reason at all, Bohns said.

Mary Catt is assistant director of communications at the ILR School.