Aaron Hernandez's murder trial will examine his tattoos and drug use

BOSTON, March 1 (Reuters) - Former New England Patriots star Aaron Hernandez's tattoos and history of drug use could be among the evidence presented at the convicted killer's second murder trial, which gets under way in Boston on Wednesday with opening arguments.

Prosecutors charge that the 27-year-old former tight end gunned down two Cape Verdean men outside a Boston nightclub in May 2012 after one of them unwittingly spilled a drink on him. Those killings allegedly came a year before Hernandez shot dead an acquaintance at an industrial park near his North Attleborough, Massachusetts, home.

Hernandez is currently serving a life sentence after being found guilty of the 2013 North Attleborough murder. The Boston case represents the second murder trial he faces in two years.

See photos from his first trial below:

Suffolk County Superior Court Judge Jeffrey Locke has approved a request by prosecutors to use photos of some of Hernandez's tattoos as evidence. Prosecutors argue that two tattoos depicting guns are references to the double murder as well as an alleged nonfatal shooting of a friend.

Hernandez's attorneys have indicated in court papers that they may call experts on use of marijuana in the National Football League and on the relationship between marijuana and violence. Hernandez's history of using marijuana and sometimes the stimulant PCP was detailed during his first trial.

Prosecutors contend that Cape Verde nationals Daniel Abreu and Safiro Furtado did not realize that one of them had brushed against Hernandez at the nightclub before he followed them outside and pursued them in a car before the fatal shootings.

See Hernandez's tattoos:

Hernandez, who has pleaded not guilty, is also charged with witness intimidation for shooting his friend Alexander Bradley in the face on a trip to Florida, after the man mentioned the murders. Prosecutors have said they plan to call Bradley, who lost an eye, as a witness to the killing of Abreu and Furtado.

Hernandez had a $41 million contract when he was arrested at his North Attleborough home in June 2013 and charged with murdering Odin Lloyd, an acquaintance. The team dropped him within hours of his arrest.

Patriots owner Robert Kraft testified at Hernandez's first trial, telling the jury that the athlete had professed his innocence and claimed to have been a nightclub at the time of the shooting.

The team's head coach, Bill Belichick, is listed as a potential defense witness for this trial. (Editing by Matthew Lewis)