Vic axe killers can't appeal: court

Two Victorian men jailed for the brutal axe murder of an autistic boy have been told they cannot appeal their convictions.

Timothy "Timmy" O'Brien, 14, was trying to defend his beloved stepfather from ambush when he was attacked and killed in January 2013.

Joel Parker Henderson, 42, and Darren Wilson, 37, were later found guilty of his murder and handed at least 20 and 26 years behind bars, respectively.

The Court of Appeal on Wednesday dismissed a bid to overturn their convictions.

On the night of the murder, Henderson and Wilson had planned to ambush Timmy's stepfather, Peter Williams, at a house in Scarsdale, near Ballarat.

A woman lured Mr Williams, Wilson's cousin, over to a house, saying she thought she had heard a prowler.

Timmy, who followed his stepfather everywhere, insisted upon going along, armed with a torch and a baseball bat.

When they arrived, Wilson attacked Mr Williams, leaping out of a bedroom and punching him in the face.

Timmy tried to protect his stepfather, striking Wilson with his baseball bat until he fell to the ground.

Armed with an axe, Henderson entered the house.

Timmy saw the weapon and started hitting Henderson with the bat, before Henderson struck Timmy with the blunt end of the axe.

Wilson took the weapon and attacked Timmy with its blade, Henderson doing nothing to stop him.

Timmy's skull was caved in and he died where he lay.

Both Henderson and Wilson tried to appeal their convictions, citing legal reasons related to their trials, but the court on Wednesday dismissed the separate bids.

Wilson also tried to appeal his sentence, because Henderson's was lower, but that attempt was also thrown out.