A smartphone biometric fingerprint scannerImage copyright Getty Images

Police in Florida have been criticised for allegedly entering a funeral home in a futile bid to unlock a dead man's smartphone.

Linus Phillip, 30, was killed while trying to escape from police at a petrol station in Largo on 23 March.

After his body was released to the Sylvan Abbey Funeral Home, his family say, two police officers tried to use his finger to unlock his mobile phone.

"It's disgusting," his girlfriend, Victoria Armstrong, said.

"So they are allowed to pull him out of the refrigerator and use a dead man's finger to get to his phone," she told ABC Action News.

Largo Police said that Mr Phillip had used his car as a deadly weapon – by dragging a police officer who had tried to get into the car – as he tried to escape.

According to Forbes, police frequently use the fingerprints of overdose victims on the TouchID fingerprint scanner on iPhones, to try to find information relating to drug dealers, and often they are successful.

But it doesn't always work – in November 2016, Abdul Razak Ali Artan rammed his car into a group of pedestrians at Ohio State University and then began stabbing people. He injured 11 people before police shot him dead.

An unlocked iPhone was found on his person – but in the hours after his death as police sought access to his phone, the iPhone went to sleep, and when it reopened, it required a passcode. Pressing Artan's finger to the smartphone did not work.