The musician was arrested in Miami on Sunday, when customs officials found ecstasy, MDMA and Viagra as Big Boi attempted to leave a cruise ship.
He was later charged with three counts of possessing a controlled substance and possessing drug paraphernalia.
Big Boi's attorney Daniel Kane has now insisted that a full investigation will prove his client's innocence.
Kane told CNN: "While Big Boi was travelling with his group and friends, a small amount of contraband was found in the collective luggage. I am confident when the entire facts are aired Big Boi will be completely exonerated."
Big Boi was reportedly able to leave a Miami jail soon after his arrest when he posted a $16,000 (£9,776) bail.
The star is currently working on his second solo album Daddy Fat Sax: Soul Funk Crusader, which is expected to be released later this year.
Watch Outkast's music video for 'Roses' below: