On his arrival at Isle de St. Marie, an unguarded and well known pirate ship named "Mocha Frigate" was at anchor in the harbour. The ship was captained by Robert Culliford, who, 10 years earlier had stolen Kidd's ship the "Blessed William" from the harbour in Nevis. Culliford's ship would have proved no match for Kidd's 34 gun warship, even in her dilapidated condition. Kidd had his chance to get even and at the same time uphold the terms of his commission to rid the region of pirates.
If you believe Kidd's trial account of these events, (at Kidd's trial conflicting accounts were heard) Kidd claimed he found himself at the mercy of his adversary after all but 13 of his own men deserted to join Culliford, and was therefore unable to attack the known pirate. Kidd alleged that Culliford then sacked and set fire to the "November", and then stripped the "Quedagh Merchant" and "Adventure Galley" of their guns, powder, shot, small arms and cables before turning his attention to Kidd.
During the melee, Kidd claimed, Culliford also seized and burned his log and threatened to kill him. Kidd then alleged that he and his thirteen loyal crew members barricaded themselves inside his cabin. How long the alleged stand off lasted is not known. Kidd claimed he eventually surrendered to Culliford. In return for whatever Kidd offered, (which is subject to speculation as Kidd did not specify the terms of his surrender) Culliford spared Kidd's life and those of his crew who had stayed loyal to him.
Strangely enough, no mention was made of booty being pillaged from any of Kidd's ships, which may indicate that Kidd could have hidden his loot on his secret island en-route to Madagascar. If Kidd did have treasure and goods in his holds, Culliford would surely have taken it and Kidd would have reported it.
Six weeks after the alleged confrontation, in June 1698, Kidd claimed Culliford set sail in the "Mocha Frigate" to resume his pirate ways, leaving the stripped "Adventure Galley" and "Quedagh Merchant" lying otherwise unharmed in the harbour. The "Adventure Galley", leaking like a sieve, was now resting on the bottom of the harbour. Kidd claimed he transferred everything he could salvage from the "Adventure Galley" to equip the "Quedagh Merchant" and then torched the "Adventure Galley". Why he should set fire to a ship that, according to Kidd, was already resting on the bottom of the harbour baffles me. What would be the point? This is only one of numerous aspects of Kidd's courtroom account that just doesn't make sense.
I believe Kidd's courtroom testimony was a complete fabrication of the truth. The concocted story was Kidd's convenient account of how he "lost" his ship, his crew, his 34 cannons and his ship's log without admitting to trading with a known pirate. Kidd's account did not explain why Culliford allegedly spared his life, or why he left the "Adventure Galley" and "Quedagh Merchant" lying stripped but otherwise unharmed in the harbour at St. Marie. Kidd's account was deemed as incredible and beyond belief.
At his trial, his prosecutors would refer to this encounter with Culliford as evidence of Kidd's collusion with known pirates. The terms of the commission required Kidd to attack all pirates.