Pc Jonathan Broadhead fired his Taser at the youngster twice within “approximately eight seconds” of entering her home in south-west London on January 21 2021, after her mother called 999.
He is accused of using force “which was not necessary, reasonable and proportionate” against the girl, referred to as Child A during his Met Police gross misconduct hearing at Palestra House in London.
The girl’s mother, Miss A, called police after Child A threatened her with a hammer and garden shears after she confiscated her mobile phone due to a safeguarding concern, the panel has heard.
Pc Broadhead said Child A was sitting in the kitchen when he and his colleague, Pc Steven Morgan, arrived and she “almost instantly leaned down and grabbed the shears and got up”.
Giving evidence on Tuesday, he said: “I was worried what her intentions were with the shears, why, as soon as she’d seen us, she’d picked the shears up. I was worried what she was going to do with them.”
In body-worn video played to the panel, he can be heard saying “Put it down now” twice as he advances into the property.
He said he gave the succinct commands “to make it nice and clear” so Child A could hear and understand.
Pc Broadhead claimed the girl could have inflicted a “huge array” of injuries and “potentially fatal” wounds with the shears, and so he pulled out his Taser after she “armed herself” and headed upstairs.
“I felt the Taser, as a distance tool, was the best way to deal with Child A, try to secure the shears to… protect us (and) anybody else in the property,” he said.
On how he felt at the time, he said: “Panicked, unsure, questioning who was in the house, what was the layout of the house, where was she going, what was she going to do?
“Worrying what was going to happen.”
He disputed that Child A ran away from officers, instead saying her movement was a “purposeful walk into the property away from us”.
Pc Broadhead shouted “Put them down” a third time and “Police officer, Taser” before tasering the girl as she tried to go upstairs.
He said he tasered her twice because he did not believe the first shot had worked.
He said: “I felt that, as she reached the bend in the stairs, that was my last possible moment to take the activation of the Taser – had she made the bend the Taser would not have the option any more.
“Moving around the corner gives her a bigger height advantage – with me going towards the bottom of the stairs, she would have been directly above me,” he added.
On Monday, the panel heard that Child A is about 5ft tall.
But Pc Broadhead said: “I was worried she could and would assault us.”
He said using his baton or Pava spray would not have been “appropriate” alternatives to his Taser.
Asked why he did not let the girl retreat upstairs, he said: “I didn’t know what her intentions were with the shears, whether there was anybody else in there, why she’d decided when she saw us to pick them up and specifically go the way she did.”
On why he did not speak to Miss A before rushing in and tasering her daughter, he said: “As the door opened, Child A armed herself and went off.
“I felt that dealing with Child A was the priority rather than dealing with and chatting to Miss A about the background.”
Reflecting on the incident, he said: “I still think the Taser was the best option I had, yes.”
Pc Broadhead admitted there was no discussion with Pc Morgan about “tactical options or creating a plan” as they drove to the address, despite them having brief details of what was going on.
In hindsight he said this was “poor planning on my part” as he was the “more experienced officer”.
Olivia Checa-Dover, presenting the case for the Independent Office for Police Conduct (IOPC) watchdog, said Child A was “presenting no immediate threat”.
The IOPC’s case is that the force used “breached the standard of professional behaviour on use of force amounting to gross misconduct”.
She said: “The starting point, in my submission, should be uncontroversial, and that is the fact this is a child, and a child of 10 years of age, should have (been) factored into decision-making.
“Where the evidence takes this is that it was not, or not to any meaningful or adequate degree.
“We know there was no working strategy. There is no mention of factors that need to be considered when you are dealing with a child in the witness statement made (by Pc Broadhead) on the same day.
“And that’s evidentially significant because it deals with other things in granular detail.”
The misconduct panel will deliberate on Wednesday before its chairwoman, Catherine Elliot, is expected to deliver her findings on Thursday.