The police had maintained that its team had visited the canteen at the state-run guest house after getting a complaint that it served "beef".
Delhi Police had violated law in entering Kerala House to "investigate" whether beef was served in its canteen and used "abusive language" against the staff, according to an AAP government-instituted probe into the police action over a week ago that had sparked a political row.
It said the entry of the Delhi Police team in Kerala House canteen on October 26 cannot be construed as a mere visit as claimed by the law enforcement agency as they had gone there with the "sole purpose of investigation" after receiving a complaint.
It echoes the views of Kerala Chief Minister Oommen Chandy that police raided the canteen without any permission from the resident commissioner of the Kerala House.
The probe said though it was amply clear to the police team during the first visit to the canteen that no beef was served, it made a second visit after a gap of 15-20 minutes which the inquiry report termed as "absolutely unethical".
The probe, conducted by Director of Animal Husbandry under supervision of Divisional Commissioner A Anbarasu, said some of policemen had used "abusive language" while shouting at staff of the canteen and created an "environment of unrest".
The police had maintained that its team had visited the canteen at the state-run guest house after getting a complaint that it served "beef". Later, police had arrested Hindu Sena chief Vishnu Gupta for allegedly making a false complaint that the canteen served "beef".
Opposition parties had reacted sharply to the police action, even calling it as an attack on federalism while Kerala government threatened legal action if the Centre does not admit that it was a "mistake".
A senior official of Delhi government said the report is being sent to the Union Home Affairs and Kerala government.
The report said as per provisions of the Delhi Agricultural Cattle Preservation Act (DACP), 1994 and rules framed under it, Delhi Police has no authority to "enter, enquire and search the alleged presence and sale of cow meat in the canteen."
It said sub-inspectors and above ranking officials of Delhi Police have power under section 11(3) of the DACP Act "to enter, stop and search or authorise any person to enter, stop and search any vehicle used or intended to be used for export of agricultural cattle".