Amber Heard has pleaded guilty to falsifying quarantine documents over the smuggling of her two Yorkshire terriers into Australia last year while visiting her husband Johnny Depp.

Key points: Two charges against Heard for illegally importing dogs Pistol and Boo dropped

Two charges against Heard for illegally importing dogs Pistol and Boo dropped Heard pleads guilty to remaining charge of falsifying immigration document

Heard pleads guilty to remaining charge of falsifying immigration document Yorkshire terriers brought in on a private jet in May, when Depp filming movie

Heard's lawyer Jeremy Kirk told the court the actress thought Depp's staff had handled Pistol and Boo's travel forms when they flew in on the private jet in April.

However, he said the paperwork had "slipped through the cracks".

The 29-year-old actress was sleep deprived and exhausted, the lawyer said, and there was "nothing in it" for Heard to fill out the form incorrectly.

Sorry, this video has expired Movie star Johnny Depp and wife Amber Heard brave media scrum

"It was a terrible, terrible mistake," Mr Kirk said.

"There was no attempt to deceive."

Prosecutor Peter Callaghan however said that distraction was no excuse.

"The laws apply to everyone," he said.

The court was told she had always intended to bring the dogs, which were vaccinated for rabies in 2014, to visit Depp, who was filming Pirates of the Caribbean on the Gold Coast.

Their arrival only came to light when the dogs were taken to a Gold Coast dog grooming salon and the visit was made public on social media.

Heard was to face two charges of illegal importation of an animal and one count of producing a false document, however the two biosecurity charges were dropped this morning.

Mr Kirk argued for no conviction to be recorded, adding Heard attracted the level of attention because of "who she is, who she's married to and what certain representatives of the Australian Government have chosen to say about it".

Video apology played in court

A minute-long video of Heard and Depp, recorded on Sunday, was played to the packed courtroom.

In the video Heard apologises for not declaring Pistol and Boo.

"Protecting Australia is important," she said.

"Australia is free of many pests and diseases that are commonplace around the world. That is why Australia has to have such strong biosecurity laws."

Depp also featured in the clip, warning others to declare everything when arriving in Australia.

"Australians are just as unique. Both warm and direct," he said.

"When you disrespect Australian law they will tell you."

The matter has been adjourned until 2:30pm.

When the couple arrived at court at 8:45am, a large media scrum of about 30 journalists and photographers was awaiting.

Around them, a number of supporters were screaming out "Go Johnny, we love you".

The saga went viral and attracted headlines across the world when Federal Agriculture Minister Barnaby Joyce said Pistol and Boo should "bugger off" back to the US or he might be forced to have them put down.

Depp helped Heard out of the car when arriving at court. ( Getty Images: Matt Roberts )

A fan tries to get Depp's signature on the way in.

Depp and Heard made their way through the dense media pack for the hearing. ( ABC News: Damien Larkins )

Heard heading into the court hearing, which was scheduled for four days before she pleaded guilty. ( ABC News )

The crowd outside the Southport Magistrates Court. ( ABC News: Damien Larkins )

The photo that gave them away - Boo and Pistol at Happy Dogz groomers on the Gold Coast. ( Supplied: Happy Dogz )

The media scrum packed tight for the arrival. ( ABC News: Mark Leonardi )