The group of young Australians -- the so-called Peru Six -- refuse to return to Peru because they believe they won't get a fair trial, the Australian Broadcasting Corp. reported Monday.
Jessica Vo, brothers Hugh and Tom Hanlon, Harrison Geier, Andrew Pilat and Sam Smith were vacationing in Peru 12 months ago and were staying at an apartment building in Lima where Rodriguez Vilchez worked.
Police initially ruled the man's death a suicide, but his brother, Wimber Vilchez, said evidence was inconsistent with suicide.
"The autopsy or the post mortem shows that my brother was covered with bruises and marks all over the front and back of his head and on the ribs and his upper torso," he said.
Wimber Vilchez alleges the six Australians were making loud noises and when his brother went to put an end to it, they beat him and threw him out the window.
An investigating judge says they are prime suspects in the homicide, the broadcaster said.
"It made me feel sick, it really did. I don't know how [they] would ever think we could do something like that," said Vo.
"It seems such a waste of everyone's time to go there because we are innocent. If we could just provide our statements they'd see that," said Tom Hanlon.