Phahlane and his team are briefing Parliament's portfolio committee on police on several complaints lodged against him by the Police and Prisons Civil Rights Union (Popcru) as well as an investigation by the Independent Police Investigative Directorate (Ipid).
He said it was proven "beyond reasonable doubt" that public funds were not used for the birthday party, but that the money was used for an official engagement while Phahlane was still division commissioner for personnel development.
The Democratic Alliance has accused Phahlane of using public money for a birthday bash, disguising it as a workshop.
But Phahlane insisted even the courts had found no wrongdoing.
"Unfortunately two people were brought before the court – those were my staff officer and a brigadier," he said.
Both officers were later found not guilty.
Phahlane said he would co-operate "with any competent authorities" investigating several allegations against him.
He did not specify whether this included Ipid.
He added: "We don't take kindly to a trial through the media."
Last month, Ipid raided Phahlane's home, allegedly in connection with a stereo system worth R80 000.
It is alleged the system was given to him by chemical company Crimetech Laboratories, a company that supplied forensic equipment to police.
Phahlane has denied this, saying he gave Ipid his proof of purchase of the sound system, and also said court action was imminent.