Bo, who stepped down as Chongqing party secretary in 2012 and is widely expected to receive a guilty verdict on charges of receiving bribes, corruption and abuse of power, made a last-ditch effort to blame his downfall on his wife's forbidden love affair with his closest aide.
He said his adviser, Wang Lijun, fled to a U.S. consulate and revealed the secrets that lead to Bo's downfall because he was secretly in love and involved with Bo's wife Gu Kailai.
They were "as close as glue and paint," Bo said, using a common Chinese expression for romantic relationships.
Wang, Bo said, was overwhelmed, writing letters to Gu and leaving his shoes and other effects where Bo could find them.
The defendant said he witnessed a scene worthy of a soap opera, as Wang delivered a love letter to Gu and slapped himself eight times in an apparent gesture of self-deprecation. Bo burst out of hiding, embarrassing Wang and sending him fleeing to the U.S. consulate.
“He knows my personality,” Bo said. “He’s harmed my family and my most primal feelings. This is the real reason he defected.”
Bo apologized for damaging the party image and appealed to the court to forgive his failings.
"I know I'm not perfect," he said. "I can be self-centered, bad tempered. I have made serious errors and mistakes."
"I had no intention of driving Wang Lijun away. Who knew one slap could create a traitor?"
Earlier in the trial, Wang testified that Bo had punched him after he revealed that Gu had murdered British businessman Neil Heywood, a crime of which she has since been convicted.
Although Bo made a confession in the early stages of the investigation, he said he was only hoping to cut a deal. He has since recanted the confession and denied all charges, but is analysts said the expected guilty verdict was essentially determined before the start of the trial.