Testing the effect of police forces' social media use

Last registered on November 10, 2025

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Pre-Trial

Trial Information

General Information

Title

Testing the effect of police forces' social media use

RCT ID

AEARCTR-0017173

Initial registration date

November 04, 2025

Initial registration date is when the trial was registered.

It corresponds to when the registration was submitted to the Registry to be reviewed for publication.

First published

November 10, 2025, 9:13 AM EST

First published corresponds to when the trial was first made public on the Registry after being reviewed.

Locations

Country

United Kingdom of Great Britain and Northern Ireland

Region

Primary Investigator

Name

Till Weber

Affiliation

Newcastle University

Contact Primary Investigator

Other Primary Investigator(s)

PI Name

Diego Zambiasi

PI Affiliation

Newcastle University

Contact Investigator

PI Name

Melissa Beckett

PI Affiliation

Newcastle University

Contact Investigator

Additional Trial Information

Status

In development

Start date

2025-11-05

End date

2026-01-31

Keywords

Behavior, Crime, Violence, & Conflict

Additional Keywords

JEL code(s)

Secondary IDs

Prior work

This trial does not extend or rely on any prior RCTs.

Abstract

This study investigates the effect of social media content shared by English police forces on viewers' support for and attitudes towards the police. We include content that focuses on (1) an outcome of police work (e.g., a drug seizure or arrest), (2) engagement (e.g., community events or neighbourhood patrols), or (3) soliciting public assistance (e.g., crime prevention or reporting). We use an online experiment with English social media users to test if viewing the social media content increases support for police forces as measured by donations to a charity affiliated to active-duty police officers. Additionally, we test if the social media content affects self-reported confidence in the police, crime concern, crime reporting intentions, spending preference, and the estimated clearance rate.

External Link(s)

Registration Citation

Citation

Beckett, Melissa, Till Weber and Diego Zambiasi. 2025. "Testing the effect of police forces' social media use." AEA RCT Registry. November 10. https://doi.org/10.1257/rct.17173-1.0

Sponsors & Partners

Experimental Details

Interventions

Intervention(s)

Intervention (Hidden)

Intervention Start Date

2025-11-05

Intervention End Date

2025-12-05

Primary Outcomes

Primary Outcomes (end points)

Our primary outcome is the amount of money given to charity in an incentivised donation task.

Primary Outcomes (explanation)

Secondary Outcomes

Secondary Outcomes (end points)

Our secondary outcomes are self-reported measures of confidence in the police, spending preference, estimated clearance rate, crime concern and crime reporting intentions. We will also elicit emotional responses (i.e., levels of happiness and excitement).

Secondary Outcomes (explanation)

Confidence in the police: “Taking everything into account, I have confidence in the police.” (5-point scale: Strongly disagree, …, Strongly agree)
Spending preference: “Do you think the Government is currently spending too much, too little, or about the right amount on policing?” (5-point scale: Far too little, …, Far too much)
Estimated clearance rate: “What do you think is the share of crimes solved in your local area? We classify crimes as solved if a suspect is recorded.” (0-100%)
Crime concern: “In general, how worried are you about crime in your local area?” (5-point scale: Not worried at all, …, Very worried)
Crime reporting intentions index (mean of three items): “How likely are you to report the following to the police? Being a victim of... Fraud/Theft/Injury” (5-point scale: Extremely unlikely, …, Extremely likely)

Experimental Design

First, participants complete a short background questionnaire.
Then, participants are randomly allocated to one of four treatments: In T0, participants are shown social media content that does not depict any police work. In T1-T3, participants are shown social media content by English police forces. In T1, the content shows an outcome of police work. In T2, the content depicts police engagement work. In T3, the content solicits public assistance.
This is followed by an incentivised donation task. Participants are asked to divide £100 between themselves and a charity with the mission to support active-duty police officers. Participants also make donation decisions to a second charity associated with harm reduction and a third charity linked to grassroot crime prevention.
Additionally, participants complete self-reported outcome measures of confidence in the police, spending preferences, estimated clearance rate, crime concern, and crime reporting intentions.

Experimental Design Details

Randomization Method

The survey platform Qualtrics will be used to randomly assign participants to treatments.

Randomization Unit

Individuals will be randomly assigned to treatments.

Was the treatment clustered?

Experiment Characteristics

Sample size: planned number of clusters

Approximately 6,284 participants.

Sample size: planned number of observations

Approximately 6,284 participants.

Sample size (or number of clusters) by treatment arms

Approximately 1,571 participants in each of the 4 treatment arms.

Minimum detectable effect size for main outcomes (accounting for sample design and clustering)

We expect a relatively small effect size (Cohen’s d=0.1), which is in line with the effect sizes reported in recent studies using a similar incentivised donation task. We aim to detect this effect size with alpha=0.05 and a power of 80%. We conducted a power analysis with Stata’s "power" command for a two-sided t-test. The expected mean and standard deviation are taken from a recent meta-analysis of charity dictator games (Bilén et al. 2021, JESA). The power analysis yields a minimum sample size of 1,571 participants per treatment arm.

Supporting Documents and Materials

IRB