The NYPD will soon allow cops to handcuff criminal suspects with their hands in front instead of behind their backs as part of the use-of-force overhaul — a change one police source called “total lunacy.”

“They want to say they’re a kinder, gentler police force by coming up with a new policy on front-cuffing. But it invites danger,” the source said.

NYPD spokesman Stephen Davis told The Post that the change — which will go into effect Jan. 1 — was part of the revision of the Patrol Guide regarding use of force.

He said suspects with “medical or physical hardships” would be candidates for front cuffing, but it would be the arresting officer’s decision.

“If someone’s in good enough shape to fight, that’s a person who wouldn’t be a candidate for front-cuffing,” he said.

But the source recalled a case from November 1989 when two detectives were fatally shot by a suspect they had “front-cuffed” — a violation of procedures at the time.

The shooter, Jay Harrison, a 25-year-old career criminal, had lifted a gun from an unsecured locker in a squad room at Queens Borough Hall.

He was left alone with his left hand cuffed to a steel bar but his right hand free so he could eat lunch, and he was able to reach into the locker.

There’s never been a reason to change the policy, So why now? It’s all politics. - Source

When Detectives Richard Guerzon and Keith Williams put him in the back of their car for a ride to Rikers, he pulled the gun and shot them dead.

“There’s a very strong reason that is indisputable on why police officers should not front-cuff prisoners, and that’s Guerzon and Williams,” the source said, adding that officers have always been able to rear-cuff perps with health issues.

“There’s never been a reason to change the policy, So why now? It’s all politics.”

Another source also scoffed at the change.

“For the last 100 years, it’s always been rear-cuffing,” a second source said, noting that suspects could use their hands — and the cuffs themselves — as weapons. “It’s a safety issue. With front-cuffing, a suspect can almost drive a car away.”

Police brass announced the change during an Oct. 8 meeting at One Police Plaza that included Commissioner Bill Bratton and other top cops and union heads.