A Kambah man accidentally downloaded child pornography from the internet among ''torrents'' of legal, adult material, his lawyer says.

Clinton James Morosi has been charged with using a carriage service to access child pornography and intentionally possessing child pornography.

The 35-year-old is also accused of possessing a small amount of cannabis, and his lawyer Bernard Collaery said his client would probably plead guilty to that allegation.

But the defence has flagged a challenge to whether Morosi intentionally possessed the images and videos, arguing he never intended to download child abuse material.

The court heard the offensive material was part of a collection of 500,000 files, of which Mr Collaery said just ''0.01 per cent'' was child abuse material.

The defence lawyer said his client would leave his computer on overnight, downloading material from the internet.

''The question is what intention was exercised if, as he suggests, he pressed the download button and allowed these types of images to be downloaded?'' Mr Collaery said.

The defence sought an adjournment, asking for details of the Commonwealth DPP's allegations.

Magistrate Peter Morrison adjourned the matter until next month.