Mulligan has enlisted the help of high-profile attorney Michael Flanagan, who represented Dr Conrad Murray in the Michael Jackson death trial.
Mr Flanagan insists that officers concluded the banking executive was not under the influence of any drugs at the time of the alleged altercation, according to TMZ.
They told the celebrity gossip website: ‘Mulligan had committed no violations of law and was not arrested. No drugs were found during a search of his person…and the officers found absolutely no evidence of drug use by Mulligan.’
A representative for the Los Angeles Police told MailOnline that no statement has been released regarding the case.
According to an initial police report, Mulligan, 53, appeared 'out of it' after officers responded to 911 calls about a man trying to break into people's cars at a drive-thru in Highland Park.
CBS Los Angeles, citing a police report seen exclusively by the station, reported that officers were told by Mulligan he was high on marijuana and had ingested ‘White Lightning,’ another term for bath salts, and had not slept for four days.
The bank executive was spotted wandering in a confused state by passers-by on May 15, 2011 at around 10.40pm.
Due to his erratic behavior, officers called a senior officer to the scene, who carried out a drug evaluation.
There was no definitive evidence of a controlled substance that the LAPD test for, according to the police spokesman.
Mulligan told officers he was 'tired and exhausted' and asked to be escorted to his car so he could collect belongings to go to the local Highland Park Motel.
When they reached the vehicle, there was a large amount of money in the car, causing officers to call for back-up as is protocol. Mulligan was then left at the motel by officers without further incident.
They saw Mulligan in the street, running into oncoming traffic. Officers called him back on to the sidewalk, but rather than comply, Mulligan assumed a ‘combative stance’, striking martial arts poses.
At that point, officers were forced to subdue Mulligan adding that a ‘use of force then occurred' before he was arrested.
Earlier this month Mulligan sued the LAPD for $50million, saying that during the 2011 encounter he was battered by the police.
Mulligan, a graduate of the University of Southern California, has worked at numerous high-profile firms, including Fox, NewsCorp, and Universal Studios.
Premiere Magazine voted him as one of the '50 most powerful people in Hollywood' and the Los Angeles Business Journal voted him 'One of the 10 most prominent bankers in Hollywood'.
According to documents obtained by the MailOnline, the Deutsche Bank executive further alleged that the LAPD officers in question were holding him hostage at the motel where he was staying as a means to steal the $5,000 he had on his person at the time.