If you were following the verdict in the James "Whitey" Bulger trial in real time, whether on Twitter, TV or radio, you might have noticed something a little unusual.

Though Bulger was accused of playing a role in the murder of 19 people, he was not charged with a single count of murder.

The 19 murders that Bulger is alleged to have committed (11 of which the jury found "proved") were considered predicate acts — criminal acts that establish a pattern and are committed in order to carry out a larger crime. 

In the Bulger case, that larger crime was racketeering.

Why would the federal government choose to prosecute Bulger for racketeering instead of murder? In short, it's because the feds don't have the power to prosecute a person for murder.

Criminal defense and civil liberties lawyer Harvey A. Silverglate explained that the federal government system has limited jurisdiction.

"In order for there to be federal jurisdiction, there must be some link between the activity and something that the Constitution explicitly entrusts to the federal government," he said. 

The U.S. Constitution doesn't explicitly empower the federal government to prosecute murder cases. In most cases, only the state can prosecute someone for a murder that occurs inside its borders. However, there are a few exceptions. For example, a murder that is committed on an military base, or a murder of an employee of the federal government, or a murder involving a violation of civil rights.

One thing the federal government is entrusted with explicitly by the Constitution is regulating interstate commerce. And, because Bulger's criminal enterprise stretched across many states and involved a lot of money, the majority of the 32 charges against Bulger were for racketeering, money laundering, and extortion.  

While the distinction may seem like an academic one, Silverglate points out that the implications could be enormous for Bulger.

"There is no question he can still be prosecuted for murder in Massachusetts," he explained.

Following the verdict, Steve Davis, the brother of one of Bulger's alleged victims, Debra Davis, said he wants the state to pursue a murder charge against Bulger.

Bulger also faces potential murder charges in two other states. Among the murders the jury said Bulger was proven to have committed were the 1981 murder of World Jai Alai owner Roger Wheeler in Oklahoma and the 1982 slaying of John Callahan in Florida. The maximum sentence for murder in those states, unlike Massachusetts, is death. 

And with no statute of limitations on murder in the United States, that means Bulger, now a convicted criminal, faces the threat of further prosecution and a potential death sentence for the rest of his life. 

Read more about the jury's verdict in the trial of Boston mobster James "Whitey" Bulger here

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