WA men lose appeal over karaoke extortion

Four men jailed over an extortion racket involving a Perth karaoke bar have lost appeals against their sentences.

The nine men sentenced over the crime came from two gangs - the Comancheros, led by Ronald Earnest Parr, and a predominantly Asian gang, led by Van Hung Phan.

They demanded $10,000 a week from the Northbridge business until covert operative "Danny" posed as the owner and had several meetings with them, which then led to their arrest.

Parr, who was considered the mastermind, was convicted after a trial and sentenced to nine years behind bars, while the others pleaded guilty over their involvement.

Vietnamese-born Phan, who was labelled the main negotiator, was sentenced to seven-and-a-half years in jail, while former Comancheros nominee Ronald Keith Cross and ex-secretary Wade Robert Hopes were each jailed for five years.

The four men took their cases to the WA Court of Appeal and among their claims was that their sentences were manifestly excessive.

But on Wednesday, their appeals were dismissed, with the judges ruling the sentences were not unreasonable or unjust.

"It cannot be inferred that the sentencing judge made any error of principle in the exercise of his sentencing discretion," the judges ruled.