Police officers reportedly caught Kevin MCEnroe appearing to make a drug transaction with another person and they were both taken into custody.
The 27 year old was allegedly found in possession of six envelopes of cocaine, 20 painkillers, 20 morphine pills and one anxiety pill, according to the New York Daily News.
Both suspects have since been charged with criminal possession of a controlled substance.
MCEnroe is due to be arraigned in court on Wednesday afternoon (16Jul14).
Former child actress O'Neal has a long history with drug addiction issues, but is said to have kicked her habit after her 2008 arrest for cocaine possession.