Toronto computer consultant Byron Sonne once built a “wave guide” to redirect microwave energy but confessed he was unable to even melt chocolate from a few inches.

He posted a wry account of his failed experiment on his “Toronto Goat Blog,” in June 2009, concluding there was “no magnetron death ray.”

But a year later, a G20 intelligence detective deliberately misled a judge when he omitted any reference to the blog in a document seeking authorization for a search warrant of Sonne’s Forest Hill home, his lawyer Joseph Di Luca argued Tuesday.

Instead, Det. Chris French used information from a random website to back his suggestion Sonne was preparing to use such a device as a “HERF gun” (a high-energy radio frequency weapon) to destroy Toronto G20 Summit security cameras, Di Luca said.

“There is a recklessness to the entire judicial authorization process and a slipshod quality to how this was crafted,” Di Luca told Ontario Superior Court Justice Nancy Spies in the second day of Sonne’s trial.

Sonne, 39, an Internet security expert dubbed the “G20 geek,” was arrested on June 22, four days before the summit of world leaders.

He has pleaded not guilty to four counts of possessing an explosive substance and one of counselling mischief.

His lawyers are trying to exclude evidence obtained by police at his home and family cottages, arguing the search warrants were obtained by deceiving the issuing judge with half truths and exaggerations.

Di Luca gave other examples of what he termed slipshod, reckless or misleading statements. For instance:

• French saw photos of a projectile launcher (or potato cannon) on a Flickr website associated with Sonne, and asked the judge to allow police to search his home to seize this device. But he had no way of knowing whether Sonne even owned one, Di Luca said.

• Other Flickr photos showed metal objects — like a bolt — and French concluded they could be fired from Sonne’s potato cannon, “a wildly speculative claim.”

In written documents, the Crown argues French’s concerns were reasonable and the defence’s “microanalysis” of his every factual assertion should be rejected.

The trial continues.