New law could keep notorious paroled paedophile Colin Humphrys behind bars

South Australia's chief prosecutor will decide within days if he'll seek to use new legislation to keep notorious pedophile Colin Humphrys behind bars.

Director of Public Prosecutions Adam Kimber says the changes, passed by parliament last week, establish a new test to be applied before someone previously detained is released.

With Humphrys now scheduled to be freed within 14 days, Mr Kimber says he will decide by Thursday if he will seek to use the new provisions, which apply to anyone unwilling or unable to control their sexual instincts.

"The amendments also give me the ability to make an application to have the release on licence of anyone previously released re-considered by the Supreme Court," the director said in a statement.

"If I make that application, the new test is to apply."

Humphrys was originally cleared for release earlier this year by Supreme Court Justice Trish Kelly but the DPP sought to overturn her ruling.

However, the Court of Criminal Appeal decided today that the original decision should stand.

Chief Justice Chris Kourakis and justices Ann Vanstone and Kevin Nicholson said Justice Kelly had acknowledged the high risk Humphrys would reoffend, but had found the conditions imposed by the Parole Board would minimise the likelihood.

The measures imposed included electronic GPS monitoring and the intense supervision of a corrections officer.

Following that ruling, Mr Kimber said he was "obliged to carefully consider a number of matters".

"Most importantly, not only the new legislation and all relevant material available to me with respect to Mr Humphrys, but also the judgment handed down today."

Humphrys has an extensive history of sexual offending against children dating back to the 1980s, including the abduction and abuse of a boy in the early 1990s and the 2003 sexual assault of a boy in a toilet block.