TORONTO -- The trial of two former senior political aides accused of illegally destroying documents related to an Ontario government decision to cancel two gas plants will go ahead, a judge ruled Thursday.

In rejecting defence arguments that the prosecution had no case at all, Ontario court Judge Timothy Lipson said some evidence exists on which David Livingston and his deputy Laura Miller could potentially be convicted.

At issue in the interim ruling, the judge said, was not whether the Crown's case was weak, but whether it had any case at all. That meant deciding only whether what the prosecution was advancing is reasonable.

"At this stage, it is not the court's function to weigh the evidence, nor to test its quality or reliability," Lipson said. "I am not entitled to make findings of fact, nor to engage in an assessment of the evidence with a view to determining the guilt or innocence of the defendants."

Lipson stressed his task was to determine whether any evidence existed to support the prosecution's case, and that any finding of guilt would ultimately depend on the Crown proving guilt beyond a reasonable doubt.

Livingston, chief of staff to former Liberal premier Dalton McGuinty, and his deputy Miller, had pleaded not guilty to deliberately and illegally destroying documents in 2012 and 2013 related to the government's contentious decision to cancel and relocate two gas plants before the 2011 election at a cost of more than $1 billion.

Lipson noted the gas plants decision "dominated political discussion" at the legislature in 2012 and 2013 and that the opposition and others were hunting for information.

Livingston was clearly alive to the information requests and at one point instructed staff in the premier's office about "double deleting" emails, Lipson said. The duo also engaged Miller's partner, Peter Faist, to actually wipe computer hard drives.

Lipson did agree with the defence on the absence of evidence to show that any emails or other documents the pair deleted had to be kept in light of freedom of information or legislature committee requests for the data.

Concluding that deleted files or emails were in fact relevant to the prosecution's case would at best amount to an impermissible "educated guess," Lipson said. As a result, he allowed the defence's directed acquittal application in part -- downgrading the charge they had committed mischief to data to one of having attempted to commit mischief.

However, the judge also found it would be reasonable to conclude that the accused did know the drives had records that should have been kept.

Lipson noted that the accused ignored explicit concerns from senior bureaucrats that records related to the gas plants would be destroyed but proceeded to have Faist wipe them anyway.

A reasonable observer could conclude the accused fraudulently obtained the administrative rights Faist needed to carry out the hard drive wiping, Lipson said.

Faist was not a member of the civil service and had no security clearance. He was also paid $10,000 by the Liberal party rather than going through a normal procurement process.

Lipson said he had considered various defence explanations for what happened, but said that didn't mean the Crown had no case.

The prosecution had already conceded that a third charge on breach of trust could not succeed and Lipson acquitted the accused on that count.

The trial will now resume Nov. 16.