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Measures and Procedure

Beliefs About Migrant Criminality
Participants read the following prompt:

[PROMPT]

Participants were then asked to estimate the percentage of undocumented migrants at the southern border who belong to each of these three groups (in random order).

We then asked participants to estimate the percentage of migrant children at the southern border who are being used by adults who are not their parents: “There have been stories of undocumented migrant adults using children (who are not their own) to gain entry at the U.S. southern border” and then asked to “estimate the percent (%) of migrant children at the southern border who are being used as props by adults who are not their parents.”

Dehumanization
We measured the dehumanization of undocumented migrants (and filler groups in randomized order) with the “Ascent of (Hu)Man” Scale (Kteily et al., 2015), which asked participants to provide humanity judgments using a sliding scale spanned by the Ascent of (Hu)Man diagram. We anchored responses at the 0 = least evolved/civilized and 100 = most evolved/civilized sides of the image. 

Anti-Migrant Policies
We assessed anti-migrant policy support with five randomized items including three policies implemented by the Trump administration (e.g., “Any person who crosses the border illegally with a child should be separated from that child for court processing”) and two policies favored by the Obama administration

Demographics
Participants answered demographic questions about their race, gender, geographic region, and political affiliation. We consider as Democrat all participants who indicated strong Democrat, weak Democrat, or lean Democrat, and we consider as Republican all participants who indicated strong Republican, weak Republican, and lean Republican.

Study 2
Method
 

Measures and Procedure
Estimations
We assessed estimates of gang members and children used as props as in Study 1.

Dehumanization

Empathy Toward Migrants
Participants indicated their empathy levels toward migrants with three questions: “How much empathy do you feel for parents whose children are taken from them as they cross into the U.S.?” “How much empathy do you feel for children who are taken from their parents when they try to cross into the U.S.?” “How much empathy do you feel for migrants at the southern border, in general?”

Anti-Migrant Policies
We assessed anti-migrant policy support as in Study 1 but with a slightly modified set of seven randomized items (e.g., “The United States should enforce a ‘zero-tolerance’ policy in which all unauthorized people crossing the border should be criminally prosecuted”

Study 3

In Study 3, we explored the relationships between (over)estimates of migrants’ illegal/immoral activity, empathy/dehumanization, and anti-migrant policy support using two interventions. To induce empathy, we used a 2-minute video (player.vimeo.com/video/288249520) depicting the emotional reunion of an undocumented mother and her child after they had been separately detained for months. Since the mother expresses a range of human-specific emotions (e.g., love, remorse, shame), we assumed that the video would also reduce dehumanization. [...] in addition to this more affective video intervention, we created a brief cognitive intervention that aimed to correct the (over)estimates of migrant criminality. In this intervention, participants made each of the two estimates, as in Studies 1 and 2, and immediately after each estimate, they were provided with the actual percentage of migrants suspected of being associated with a gang (∼1%) or the actual percentage of children suspected of being used or trafficked by adults who were not their parents (<.1%) from DHS statistics. We tested these intervention strategies in an experimental paradigm with five conditions: video only, statistical correction only, video + statistical correction (two versions with order counterbalanced), and no intervention control.

Measures and Procedure
After providing consent, participants were randomly assigned to one of five conditions: statistical correction only (n = 198), video only (n = 189), statistical correction + video (Order 1; n = 190), video + statistical correction (Order 2; n = 187), and control (n = 194). In the statistical correction condition, participants first provided the same gang member and children used as props estimates as in Studies 1 and 2, and immediately after providing their estimates, they were shown the actual DHS data as described above. In the video condition, participants watched a video, as described above, and then provided the two estimates about gang members and migrant children but did not receive the DHS data. In the control condition, participants made estimates but did not receive DHS data and were not shown the video. All participants then completed the same empathy (α = .90), dehumanization (multi-item: α = .91), and anti-migrant policies (α = .83) measures as in Study 2