The police watchdog is to investigate the use of a Taser on a man who suffered minor bruising after falling 8ft from a porch roof.
The Independent Police Complaints Commission (IPCC) said the inquiry would examine the decision-making of officers who detained the man in Worcester on August 10.
Police apprehended the 44-year-old man - who had possession of a knife and a hammer - under the Mental Health Act after being called to a house in the Warndon area of the city at around 1.20pm.
Officers arrived to find the man, a relative of the occupants, damaging roof tiles and dropping them to the ground.
In a statement, the IPCC confirmed that the Taser was deployed at about 2.30pm after the man remained on top of the porch.
IPCC Commissioner Rachel Cerfontyne said: "Our independent investigation will focus on the overall police management of this incident, together with the actions and decision-making of the officers involved.
"We will consider the appropriateness of the use of Taser and what tactical options were available to police in the circumstances."
West Mercia Police referred the incident to the IPCC, which has made contact with the man's family, on August 11.