Police plans to only attend emergency mental health incidents if there is an “immediate threat to life” is alarming experts.
The Met Police’s new rule for 999 mental health calls will come into force in September.
Commissioner Sir Mark Rowley said officers should be focused on fighting crime and patients needing medical help are failed when police attend instead.
Zoe Billingham, an ex- Inspector of Constabulary and Fire and Rescue, said those in crisis need to be cared for in a health setting but police have always been the first responder.
“There is simply no other agency to call right here, right now. So yes, I’m alarmed.”
Ms Billingham, who is now head of an NHS mental health trust, said: “The mental health system is stretched to almost breaking point.
“The idea that mental health practitioners can step into the vacuum left by the police. Well, it’s ridiculous.”
Sarah Hughes, of charity Mind, said mental health crises are “incredibly complicated” and knowing if a life is at threat can be very difficult.
She said the Met and the NHS must work out a plan to address this.
Ken Marsh, of the Metropolitan Police Federation, said officers spend too long “babysitting” people, waiting for them to be treated, but “it’s not for the commissioner to say whether my colleagues can or can’t attend”.
The Met said health services must take chief responsibility for the care of the mentally ill.
