Since the emergence of footage showing Ray Rice assaulting his then-fiancee at an Atlantic City casino, NFL officials have maintained they sought elevator surveillance tape from local law enforcement and were unable to obtain it.

This contention has been met with skepticism however, and with good reason. Each NFL team employs a head of security who is expected to develop relationships with both police and the management of establishments frequented by players such as hotels, night clubs, strip clubs and casinos.

In 2009, the NFL wrote up a job description, obtained by CBS News, that defined for teams the responsibilities of the team security director.

The description says the director is required to conduct: "personal visits to local casinos, night clubs, etc. requesting the cooperation of the establishments' management in the event a player or team employee is perceived as a potential problem."

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A former NFL team security director who does not want to be identified told CBS News that in his career, there was never a case where he sought surveillance tapes from hotels, nightclubs or local law enforcement and did not obtain it.

The NFL told CBS in an email that personal visits to casinos are "for an early warning if a player or employee might be engaging in conduct that puts the player or employee at risk."

The job description also says "becoming a close and trusting liaison with federal state and local law enforcement agencies as well as other government entities, such as DMV, is essential." Security directors are required to "establish and maintain effective liaison on a confidential and professional basis with federal, state and local law enforcement officers and other public safety authorities."

The NFL responded to this in an email saying: "Having a professional relationship with law enforcement officials on all levels is helpful when an incident occurs to be able to attempt to determine the underlying facts as soon as possible. At times this is not possible if the information cannot be shared outside of the law enforcement agency realm."

The description lists under necessary experience "at least ten years prior experience in law enforcement in the area of the team's location strongly preferred." For example, Darren Sanders, Ravens team security director, is a former Baltimore City police detective.