"In parties where slavery system is prevalent, a worker cannot raise his voice against his leader. But, the AAP is untouched by this," he told reporters here.
Sanjay Singh was responding to questions on leadership abilities of APP convenor Arvind Kejriwal in the backdrop of senior leader Shanti Bhushan's outburst against him.
The AAP was the only political party in which all members have freedom to raise their voice, Singh said.
He said in the Delhi Assembly polls last year the party secured 29 per cent votes while in Lok Sabha elections, it got 39.5 per cent.