A man who repeatedly stabbed a kangaroo was too drunk to remember where or when the "senseless and unfathomable" attack happened, a Perth court has been told.

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Key points: Ricky Ian Swan was charged in September after police discovered video of the incident

Ricky Ian Swan was charged in September after police discovered video of the incident Swan's lawyer told the court his client had become a "pariah in the community"

Swan's lawyer told the court his client had become a "pariah in the community" The magistrate said a prison term was likely, but it could be suspended

Ricky Ian Swan, 28, has pleaded guilty to two animal cruelty charges in relation to the attack, which was filmed and posted on social media earlier this year.

He was one of four men charged in September with using a number of weapons to fatally torture two kangaroos in May and June.

During sentencing submissions, the police prosecutor told the court the video showed Swan chasing the kangaroo before it fell.

Swan then used a large knife to stab the kangaroo to the head and neck 22 times.

He swore at the animal and verbally abused it as it tried to escape.

The prosecutor said Swan then stepped back and kicked the kangaroo in the head before spitting on it.

Other men could be heard in the video laughing and encouraging Swan.

Swan has become a pariah: lawyer

Swan's lawyer John Hammond told the court that while his client admitted the attack, he was so drunk that he did not know when or where it occurred.

Lawyer John Hammond (left) said jailing Swan would interfere with his rehabilitation. ( ABC News: David Weber )

Mr Hammond described the attack as "senseless, brutal and unfathomable", and said his client had been "publicly shamed through social media".

"Mr Swan is a pariah in the community," he said.

Mr Hammond said Swan understood the anger and had determined "this will never happen again".

He told the court the incident had cost his client his relationship with the mother of his child.

Mr Hammond also said Swan had stopped drinking alcohol, and removed himself from the rest of the group who were associated with the incident.

He argued sending Swan to prison would interfere with his prospects for rehabilitation.

Watch footage, police urge magistrate

The police prosecutor called on the magistrate to watch the video before he decided on a sentence.

Swan and three others were charged after two kangaroos were tortured and killed. ( ABC Open contributor Alex Kydd )

He said if Swan drank to the point where he could not recall the incident, it would have also had an impact on his motor skills, but he said in the video, Swan was demonstrating "good motor skills".

The prosecutor described it as a "heinous" attack, carried out while "all his mates laugh".

The magistrate adjourned sentencing to December 7, saying a prison term was likely but he could decide to suspend part or all of the term.

Outside court, Jehni Thomas-Worth of the Animal Justice Party called for Swan to be locked up.

Animal cruelty campaigner Jehni Thomas-Worth says Swan deserves to be jailed. ( ABC News: David Weber )

"We think that's appropriate and we would be looking for a penalty that sends a really strong message that animal cruelty is never okay in a civilised society," she said.

"I feel that jail time is warranted."

The ABC decided not to publish heavily blurred versions of the kangaroo torture footage released by police.