The Station House Officer, an Assistant Sub Inspector and a Head Constable, all posted at Dhabha Police Station, had been suspended with immediate effect, Ludhiana Police Commissioner Ishwar Singh told reporters.
The action was taken against them for delaying the lodging of an FIR against the accused for 12 days, he said.
A Dalit woman was thrashed publicly on April 3 by some persons at 36 Foota Road, Singh said.
A Special Investigating Team, headed by a woman IPS officer, had been formed to probe the incident.
National Commission for Scheduled Castes Vice-Chairman Raj Kumar Verka went to spot and sought a report from police.