Original subtitles

Tonight, the murder of a notorious Mob kingpin.

Sam Giancana is the very personification

of the Mafia in America in the 1960s.

He's not only the head of the Chicago Outfit,

he is America's celebrity gangster.

He is known to hobnob with a lot of Hollywood celebrities

like Frank Sinatra and Marilyn Monroe.

When Sam Giancana's murdered,

it's front-page news.

But 50 years later,

the identity of Sam Giancana's killer

remains a mystery.

Solving Sam Giancana's murder

could open up a Pandora's Box.

With every Mob murder,

it's never one thing.

It's always a combination of things.

Now we explore

the top theories surrounding the assassination

of a Mob legend.

Everyone benefits from Sam Giancana's murder.

Police think that this is a Mob hit,

but maybe the CIA had something to do with it.

Giancana was killed

before he can share everything he knows.

There's someone who doesn't want him to talk.

Why was Sam Giancana killed, and who ordered his murder?

June 19th, 1975.

Shortly before midnight, police respond to an emergency call

from a modest home in Oak Park, Illinois.

At the scene, they find

a dead body in a pool of blood.

This man has been shot seven times.

Once in the back of the head, five times in the neck,

and once straight through the mouth.

When police start to investigate the scene,

they noticed $1,400 in his pocket.

And behind the body is a pan of partially cooked sausages

that are still on the stove.

So they think, "Okay,

well, this wasn't a robbery gone wrong."

They quickly realize that this is

not just your average victim.

This is Sam Giancana,

one of the bosses of the Chicago Outfit.

He's a household name.

He's in the papers all the time.

He's on TV.

He's dating movie stars.

He's hanging out with Frank Sinatra.

But all the while, people also know that he's the mobster.

This is one of the biggest Mob hits in American history,

and a lot of people do seem to benefit

from Giancana's death.

He's connected to everything,

and maybe someone wants to take out Giancana

because of what he knows.

The Chicago Outfit, the federal government, the CIA.

There's so many people

that would've been happy to see him gone.

And there really aren't any obvious clues

as to who the killer was

or what the motive was for the shooting.

So what we're left with

is a mystery that is now over 50 years old.

But Giancana's past as a Mob kingpin

provides a long list of potential suspects and motives.

Sam Giancana's born in 1908.

He grows up in the Little Italy section of Chicago

known as "The Patch."

This is kind of a poor, run-down area of the city,

and he doesn't have a great childhood.

So Sam, at an early age, turns to a life of crime.

The police believe by his early 20s,

he may have killed already three men.

Many folks simply called him "Mooney,"

which is another word for being crazy.

Giancana is someone who's very willing

to play into this idea that he's crazy.

This is really a persona that he builds,

a way to seem tough.

Al Capone allegedly took a liking to a young Sam Giancana,

and he was viewed as a rising star in the Chicago Mafia.

A famous crime associated with the

Chicago Outfit is the Saint Valentine's Day Massacre.

Not only is it alleged that Sam was there as a driver,

but also as a shooter.

In 1931, Giancana's mentor, Al Capone,

is arrested for tax fraud and sentenced to prison.

Giancana spends the next 20 years looking to replace him

as the head of the Chicago Mob.

Sam is rising through the ranks,

and by 1957, he is the head of the Chicago Mob.

They expand their empire under Sam's control

outside of Chicago.

They start taking over not only Las Vegas

but all the way down to Cuba.

Sam and the Outfit are raking in millions of dollars a year.

Sam Giancana is the epitome

of what it meant to be an American crime lord, Mafia Don,

and he controlled a national syndicate

that was second to none.

Everybody in America knew who Sam Giancana was,

and he loved that, and he ate it up.

But in the late 1950s,

Giancana makes a fateful decision.

He becomes directly involved with the federal government.

Outside of traditional organized crime,

he has a relationship with the CIA.

He's allegedly taking meetings with JFK

while he's president.

Giancana was trying to play everything against the middle

and expected that the White House

would take a kinder approach to organized crime,

but it was the exact opposite.

He has been connected to organized crime

essentially from his childhood,

and the Feds want to find out exactly what he knows.

In 1965, after years of trying,

federal agents believed they finally found a way

to bring down Giancana.

They put him before a grand jury

investigating the Chicago Mob's alleged racketeering

and narcotics operations.

They give him immunity from prosecution.

They say, "If you talk, you're not gonna get prosecuted.

You don't have to plead the Fifth,

and you're gonna be okay."

They ask him questions, he doesn't answer them,

and he winds up being put in jail for a year

for contempt of court.

But the other members of the Mafia

don't like this public attention at all.

After Giancana is released from prison,

he ends up going into exile in Mexico.

In 1974, he gets deported back to the United States,

and upon his arrival, he's subpoenaed.

He's been called in to testify for a US Senate inquiry

looking into the CIA's activities,

specifically the possibility that the Mob

worked with the CIA to kill Fidel Castro.

That caused grave concern from a lot of very powerful,

dangerous individuals.

On the night of his murder,

Giancana throws a party at his home in Oak Park.

All of the guests leave by 10:30 p.m.

Living upstairs is Joseph DiPersio, who's 82 years old.

He lives there with his wife,

and they're kind of like the caretakers for Sam

and the property.

Around 11:00 p.m. DiPersio calls down to Giancana

just to do a quick check, make sure he's doing all right,

but there's no response.

So DiPersio heads down to the unit.

He walks down into the basement kitchen,

and Giancana's on the ground, blood everywhere.

He immediately calls the police.

The police come and question DiPersio.

He doesn't have a lot of answers.

He doesn't even hear the shots being fired.

Police start to piece things together,

and one of the early theories that emerges

has nothing to do with Mob business.

It's all about his personal life.

Oddly enough, one of the clues

that leads investigators down this path

is that pan of partially cooked sausages.

He had just recently had gallbladder surgery.

And the last thing you wanna do

after having a surgery like that

is eating very greasy, very fatty food.

Whoever those sausages were for, they're not for Giancana.

He was preparing this meal for somebody

that he cared about and trusted enough to turn his back to.

It shows you how much he had let down his guard,

that somebody was there that he felt comfortable with,

that he wasn't afraid of,

but the way that the murder was carried out

suggested a lot of anger and animosity.

Looking at the overkill of this crime,

seven shots to the head, one in the mouth,

this seems like something personal,

not a professional hit.

In 1977,

FBI investigators learn of a possible reason for such anger.

A source tells the Bureau that Giancana was having an affair

with the wife of Chicago mobster Tony Spilotro.

This would not have been the first time

that he slept with another mobster's wife.

Giancana is a notorious womanizer,

and Nancy Spilotro was considered

to be quite the knockout.

Tony Spilotro was this little 5'3"

demonic crazy man that was running around Chicago,

putting people's heads in vises

and popping people's eyeballs out,

and getting a reputation for extreme violence.

If all of this sounds familiar,

it's because Joe Pesci's character in Casino

is said to be based off of Tony Spilotro.

He's really known for his ruthless behavior.

And Tony Spilotro at one time

lived a couple blocks from Sam Giancana.

He knew how to sneak between the backyards

to get into his house.

If Giancana betrayed him by sleeping with his wife,

you can imagine that this would clearly send Spilotro

just flying into a murderous rage.

While Tony Spilotro

may have had a strong motive,

some claim there's one detail that doesn't add up.

Despite the initial suspicions pointed at Spilotro,

a lot of people are skeptical about that theory.

In 1975, at the time that Giancana was murdered,

Spilotro was not a full-time resident of Chicago.

He was living full-time in Las Vegas.

And Sam Giancana knows that

Tony is a violent psychopath.

He certainly wouldn't have his back to him

cooking him sausage and peppers.

In 1965, Sam Giancana spends a year in prison

for refusing to testify against the Mafia.

However, once he's released,

he finds that he's not welcome back in Chicago.

The leadership of the Chicago Outfit

thought maybe it's time that Sam move on

'cause he was more of a liability than he was an asset.

He's exiled to Mexico,

and Sam is not retired at this point.

Sam continues to be Sam,

and Sam is very good at making money.

A lot of mobsters think very small.

Sam Giancana was a mobster who thought big.

The world was his oyster.

He starts getting involved with Mexican casinos

and bringing in money through them,

and ultimately throughout Central and South America.

And then he extends to other crimes like prostitution

and narcotics, extortion, kidnapping,

everything else you could think of.

According to the book Double Cross,

which is written by members of the Giancana family,

Giancana starts getting involved in narcotics trafficking

with men from Colombia,

who will later go on to become the Medellin Cartel,

which is led famously by Pablo Escobar.

He's raking in millions from narcotics,

and then he goes even further.

He extends his reach to the Caribbean

and even the Middle East.

He opens up offshore gambling boats.

He's making millions and millions of dollars,

and he's not giving one penny to the Chicago Outfit.

This does not sit well with organized crime groups.

In Italian-American organized crime,

even if you are an individual earner,

that money still needs to go back to your crime family.

"It doesn't matter if you're doing it out of state.

It doesn't matter if you're no longer our leader.

You belong to us until the day you die."

He tells him, "I'm not giving you anything.

I made money for you.

You sent me down here to Mexico.

I'm gonna continue to make money for myself

and for my family."

The Mob was furious with Sam for not cutting them in

on all the money he was making in Mexico.

At the same time, the Mexican government

wanted to become friendly with Cuba

and was concerned that this American

had been attached to a plot to kill Fidel Castro.

The authorities came to his place in Mexico,

and they literally arrested him in his pajamas

and sent him back to Chicago.

Even when Giancana returns

to the Chicago Outfit's territory in 1974,

he refuses to pay tribute.

There were a lot of people in Chicago

when he came home

that felt someone needs to go sit with Sam Giancana

and tell him the rules of the game again.

"He might have forgotten them, and we gotta remind him."

There is physical evidence that ties the Chicago Outfit

potentially to this crime.

In the initial investigation into this murder,

it did not look like a Mob hit

because the shooter used a .22-caliber pistol.

Just doesn't seem like a Mob gun.

The Mob, up to that point, used larger caliber weapons.

They're famous for using a Tommy gun,

which shoots .45-caliber.

Al Capone himself carried around a .45-caliber Colt 1911

that he called "Sweetheart."

However, in 1977, Time magazine releases an article

which talks about how, from 1975 to 1977,

the .22 seemed to be the preferred weapon for Mob hits.

In August of 1975,

landscapers in a town called River Forest, Illinois,

happened to find in the woods

a discarded .22-caliber pistol.

River Forest is pretty much right next door to Oak Park,

where Sam Giancana lived and was murdered two months prior.

And this particular ...22 has been modified

with a homemade silencer.

If we add a silencer to a .22-caliber handgun,

we can get that shot down to, like, 30 decibels,

which is about like the sound of like a whisper.

And so this would explain why

DiPersio doesn't hear anything.

It's not because he's old,

it's not because he's watching TV.

It's because of that silencer.

They did a ballistics test on this weapon,

and it was the weapon used to kill Sam Giancana.

The location of the discarded gun

may point to one Mafia triggerman in particular.

If you're gonna use that gun,

then you've gotta come in close.

So it's believed that Sam was killed

by someone he knew really well.

And interestingly, the gun is found on a road

that would lead you from Sam's house

to one of his closest allies, Dominic Blasi,

also known as "Butch."

Blasi, he did live in River Forest

and was probably Sam Giancana's most trusted soldier

and confidant, a guy that he trusted with his life.

Blasi is somebody that has literally been

by Giancana's side for decades.

He actually was one of the pallbearers

at Sam Giancana's funeral.

It was the common perception by both the press

and local law enforcement

that Butch was the one who killed Giancana.

When police question him,

he swears that he was there earlier in the evening,

but that when he left, his friend was still alive.

He always denied it and was pretty adamant in his denials

until he died in the early '90s.

But they always tap your best friend

to kill you in that world.

And Blasi was Giancana's best friend.

Whether Blasi was the actual gunman or not,

the question now becomes: what was the reason behind it?

What is the motive?

One of the best motives we've got comes in the early 2000s

during testimony by Nick Calabrese,

who was a longtime hitman for the Chicago Outfit.

He claims that the

Chicago Outfit's main issue with Giancana

was not paying them their cut.

The problem with this, though,

is: why was this hit so personal?

Why was there this level of overkill?

He's shot in the back of the head,

that would've killed him,

but then he's shot five more times in the neck

and the one shot in his mouth.

A lot of researchers insist

that what happened to Giancana was a Mob hit.

But the nature of it wasn't over money.

The coroner's report on the 1975 murder

of Sam Giancana indicates he was first shot

in the back of the head.

Then the shooter delivered six more bullets

into his face and neck.

It's a signature of the Mafia

that when they are gonna kill somebody

who they believe is snitching to the government,

to deliberately put a series of bullet shots

around his mouth.

That last shot, that coup de grace,

is basically saying, "Hey, keep your mouth shut,"

and it's a warning to others to also do the same.

The Giancana family has been relatively vocal

that Giancana's murder

really had nothing to do with the money.

It had to do with the fact that he was being subpoenaed

in front of the Church Committee.

The Church Committee is the Senate committee

led by Idaho Senator Frank Church

that is tasked with investigating the CIA,

specifically whether there was any collusion

between the CIA and the Mafia.

Within months

of returning to Chicago from Mexico,

Giancana is told he's expected to appear under oath

before the Church Committee.

Giancana is somebody that has a track record

of not ratting anybody out.

In the '60s, he's jailed for a year for contempt

because he doesn't say anything.

But by 1975, Giancana has been painted into a corner.

He's tried to plead the Fifth, but there's no way to know

whether the Senate will let him get away with that.

Does he wanna risk being thrown in jail for another year?

This is a 67-year-old man.

It might be Giancana doesn't wanna risk

having to go to prison again

because he doesn't have that much life left.

So it's very possible that he's going to try

a whole nother tactic in front of the Church Committee,

and that might be telling the truth.

Giancana's death happens just five days

before he's set to appear.

All of this ties into the idea of the code of Omerta.

Omerta is the oath of silence that you take

when you become a member of the Mafia.

To break Omerta is to basically sign your own death warrant.

The Mob is afraid of what's coming next,

that he may actually say something.

I mean, he's an old-school gangster.

He might have kept his mouth shut,

but seems like an easy answer just to take him out.

As a longtime member of the Chicago Outfit,

Giancana's fate rested in the hands of one man.

Tony Accardo.

Even when Sam Giancana was boss,

there was still a boss above the boss,

and that boss was Tony Accardo.

Nobody in America held the amount of power,

the amount of influence that Accardo held

in that time period.

Tony Accardo witnessed Al Capone,

this larger-than-life figure

who winds up drawing a great deal of attention to himself.

And Tony Accardo realizes that he should keep your head low.

He wanted to be the boss without holding the title.

So he created all of these acting bosses and street bosses

and day-to-day bosses that would run the family for him.

Despite Sam Giancana the boss of the Outfit

in 1957, Accardo is actually the real guy calling the shots,

and Giancana is just sort of the face of the Outfit.

Accardo spared Giancana's life in 1966

by exiling him to Mexico.

When Giancana returns in 1974 and is immediately subpoenaed,

the real head of the Chicago Outfit

may have been less forgiving.

When the FBI gets involved

in the investigation of Sam Giancana's death,

they immediately looked to Tony Accardo,

and they identify him as a potential suspect.

Accardo was very unhappy with the idea

that Giancana was now back in Chicago,

and whoever killed Sam Giancana

had to get the okay of Accardo.

But it turns out that he may have had

a lot more to do with it than just orchestrating the affair.

In the early 2000s,

the FBI learns that Chicago Outfit hitman Nick Calabrese

and his nephew Frank Calabrese, Jr.

are both willing to turn state's evidence.

They spilled the beans on a lot of unsolved murders,

and that turned into the biggest

Mob prosecution in Chicago history.

Operation Family Secrets.

Nick Calabrese goes to the FBI

and tells them one of the biggest

juiciest secrets of all time.

According to him, Tony Accardo

felt strong enough about Giancana

that he wanted to do his own housecleaning.

It's an extraordinary claim.

Tony Accardo hadn't just authorized

the hit on Sam Giancana.

He had carried out

the hit on Sam Giancana.

If Accardo went out of his way to commit this hit himself,

this is big.

Mob bosses do not commit their own hits.

It is likely that Accardo believed

that Giancana was about to blow everything wide open.

Yeah, he was old.

He might have looked like your grandfather,

but he could still pull a trigger.

This theory makes sense.

Accardo is another person

who Giancana probably would've trusted,

would have likely allowed

willingly into his home late at night.

Alongside Giancana,

the Church Committee also subpoenaed

two other famous Mafia associates.

Teamsters boss Jimmy Hoffa and mobster Johnny Roselli.

Jimmy Hoffa was friendly with Giancana

and Roselli, and he was supposed to testify

at the Church Committee

about six weeks after Giancana was murdered.

Jimmy Hoffa ended up disappearing

and never being found.

Johnny Roselli does testify, and he just drops a bomb.

He says that the Mob was actually working with the CIA.

Until this point, this is all rumors.

This is the first time that we're actually confirming

that there is a connection between the CIA and the Mob.

After testifying, Johnny Roselli goes missing.

He's eventually found

dismembered, death by asphyxiation,

in a 55-gallon oil drum floating in the bay,

not far from Miami.

Sam Giancana, Jimmy Hoffa, and Roselli.

All three of them murdered either before they testified

or after they testified.

This seems to suggest that

the Mafia was willing to silence anybody

who was willing to cooperate with Congress.

So the message was clear.

You don't break the code of silence.

The murder of mobster Sam Giancana in June 1975

comes at a time of intense scrutiny

on government corruption in America.

President Richard Nixon has resigned

in the Watergate scandal,

and illegal activity by American spy agencies

is being exposed by the media.

Some believe that Sam Giancana's murder

wasn't just about protecting Mob secrets.

Is it possible he was killed to protect the CIA?

After the Watergate scandal,

one of the things that came to light

was the improper use of CIA surveillance

and things of that nature.

And so the Church Committee was set up

to oversee what was going on with the CIA.

Today, the Church Committee is considered

to be one of the biggest oversight investigations

in all of US history because they uncover a series of plots,

including the plot to kill Fidel Castro

by the CIA and the Mob.

These alleged ties between the CIA and the Mafia

lead to the Church Committee

calling people like Johnny Roselli

and Sam Giancana to testify.

In June of 1975, the CIA is in big trouble.

They know exactly what they've done,

and they know that it's about to all come out.

So not only we have the Mob

not wanting Sam Giancana to talk,

but we also have the CIA not wanting him to expose

that relationship between that.

There are a number of people,

including Giancana's oldest daughter, Antoinette Giancana,

who have claimed that the CIA was somehow involved

in the murder of Sam Giancana.

So we're in the midst of the Cold War,

and both the Eisenhower and Kennedy administrations

are very concerned about this charismatic revolutionary,

Fidel Castro, who aligns closely with the Soviet Union.

Before Fidel Castro took control of the Cuban government

in the 1950s, Mafia figures own most of the major casinos

and hotels in Havana.

Mobsters are essentially kicked out of Cuba

during the revolution,

and Fidel Castro becomes a common enemy for the CIA

and the Mafia.

The CIA felt like the best people to kill Castro

were the most dangerous killers

that they could find on the streets.

This was an unholy alliance.

Conducted in total secrecy,

this partnership becomes known as Operation Mongoose.

We'll never know for sure what Giancana would

or would not have said during his testimony,

but due to Roselli's testimony,

we do get a very clear picture

of the collaboration between the CIA and the Mob.

Roselli tells an extraordinary story

that has the nation on the edge of their seats.

He was recruited by the CIA

in a plot to assassinate Fidel Castro.

And the two key players in this are Roselli and Giancana.

Sam Giancana feels that the CIA

and the Mob are two sides of the same coin.

They both want the same thing,

and they're both not above murder.

Johnny Roselli and Sam Giancana

ran a casino in Havana known as "Sans Souci,"

and so they claimed that they still had contacts in Cuba

that could get close enough to Fidel Castro.

During Johnny Roselli's testimony,

he says that the CIA was willing to pay these mobsters

$150,000, which is $1.6 million in today's money.

Giancana and Roselli actually hire someone

to put poison pills in Fidel Castro's food.

The assassin winds up backing out.

When the poisoning fails, then Roselli and Giancana think,

"All right, well, let's bring in some armed commandos

to assassinate him."

But that didn't work either.

The CIA documents are declassified

several decades later,

and you just walk through the documents,

you go, "Oh, Roselli was right.

Roselli was right."

The assassination attempts on Castro fail.

But we do see other collusion between Sam and the CIA.

At this time, he's dating Phyllis McGuire,

who's a musician, a national celebrity.

He believes that Phyllis McGuire is cheating on him

with comedian Dan Rowan.

The CIA bugged the bedroom of Dan Rowan

to appease Sam Giancana.

Now you have not only the CIA working with gangsters,

you have the CIA help a gangster deal with

an emotional problem with his girlfriend.

So what we're looking at in 1975

is that this direct testimony of Giancana

might simply blow the top off this story.

Essentially, Giancana has the power

to completely take down the CIA.

The CIA might wanna take out Giancana

before he can take out them.

The media and the public really quickly

start to draw a connection between the CIA

and Giancana's murder.

If all of this information

was being presented to the committee,

who else could it possibly have been?

Case in point, the Time magazine article,

which talked about how the .22-caliber pistol

was becoming the preferred weapon of choice for Mob hits,

also points out that the .22-caliber

has been the pistol of choice for the CIA

for years and years.

It reached the point where Frank Church

felt the need to come out and make a statement

that these theories that are being bandied about

couldn't be further from the truth.

They do uncover several other assassinations

orchestrated by the CIA,

but when it comes to the death of Sam Giancana,

Senator Church says it's probably Mob-related.

Despite these denials, it makes sense.

I mean, it would be certainly something

you'd want to investigate.

In 1975,

Sam Giancana is subpoenaed by the Church Committee

to testify about the CIA's involvement

with organized crime to kill Cuban dictator Fidel Castro.

But the committee is also tasked

with investigating the possible connection between the CIA

and one of the most consequential events

in US history,

the assassination of President John F. Kennedy.

It's something that is

one of the darkest days in American history,

and we still don't know

60 years later what exactly happened.

In 1964,

President Lyndon B. Johnson creates the Warren Commission

to investigate the assassination of John F. Kennedy,

and they conclude that Lee Harvey Oswald

is a lone actor in the assassination.

No one else is involved.

An awful lot of people

were bothered by the Warren Commission

not looking at other scenarios,

and argued that there were more plausible theories

than the lone gunman.

And one of them has to do in part with the idea

that Sam Giancana was involved.

By bringing Giancana to Washington in 1975,

these investigators were hoping to find out

whatever Giancana may know about Castro,

but while they're at it,

they could also ask him about the JFK assassination.

It's really not a crazy conspiracy theory,

the way that sometimes it's made out to be.

'Cause we know there were quite a few people

that had connections to Giancana

that were within the radius of that assassination.

Imagine if Giancana testified

and said, "Hey, not only did the CIA use me for Castro,

but they also used me to kill JFK."

Now, whether it is the government

or the Mafia that killed him,

either way, Sam dies because he knows too much.

Most everyone is in agreement that Lee Harvey Oswald

is the one who shot the president.

But did he really act alone?

There is a lot of strong evidence

that maybe the Mafia is also involved.

You sound crazy connecting all the dots there,

but it makes sense.

Lee Harvey Oswald grows up in New Orleans.

His uncle is a bookie who works for Carlos Marcello,

who is in charge of the Mob in New Orleans,

and a friend of Sam Giancana.

Lee Harvey Oswald, when he is a teenager,

is mentored by this person, David Ferrie,

who is also a private investigator

that works with Carlos Marcello.

After the assassination of Kennedy,

Oswald was murdered by Jack Ruby,

who was a well-known Mafia associate of Giancana's.

In 1975,

after Johnny Roselli testifies before the Church Committee,

his lawyer floated that Johnny

would not only be willing to talk about Castro,

but he also knew something about the JFK assassination.

And it was at that point

that Roselli winds up being murdered just like Giancana.

The really interesting twist here is that Sam Giancana

and the Mob helped get President Kennedy elected.

It's pretty much acknowledged historically

that Sam Giancana helped the Kennedy campaign

both in West Virginia and to some degree in Illinois.

With the election there,

Giancana was telling other mobsters,

"I'm supporting Kennedy

because I think he'll go easy on us."

Sam Giancana does all this work behind the scenes

to get John F. Kennedy elected president,

expecting that his life is gonna get easier,

and it does not.

The Mob became very angry and bitter

at the fact that almost immediately

when Kennedy got into office,

he came after the Mafia with an assault

that had never been bigger or more widespread.

A year later, in 1961,

JFK's younger brother Bobby Kennedy,

who was serving as Attorney General, goes after Jimmy Hoffa,

who's the head of the Teamsters,

which has connections to the Mob.

RFK also goes after New Orleans mobster Carlos Marcello,

who gets deported to Guatemala.

So Giancana allegedly vows to take revenge on JFK.

Giancana was known as a very violent guy,

one of the most violent people that the Chicago Mob

had ever known, that you don't fool around with Sam Giancana

or you're gonna find a bullet in your head.

In 1992, Sam Giancana's brother

and his godson publish Double Cross.

The book claims to reveal the Mob boss's

most shocking secrets, including what he allegedly said

about the Kennedy assassination.

In his book Double Cross,

Chuck Giancana says one day Sam said to him,

"Look, we," meaning "we," the Mob, and the CIA,

"took care of Kennedy together."

He states that Sam told him

that Lee Harvey Oswald was a CIA plant,

and that it was Giancana

that ordered the murder of John F. Kennedy.

So to break it down in its most simple form,

Oswald was the patsy,

and then Ruby was the guy sent to take him out.

And that's the typical Mob protocol.

You assign somebody to do the job,

and then you assign somebody to get rid of the guy

that did the job.

There's no way for Chuck Giancana

to corroborate his story,

and there's no way that we will ever know

what Sam Giancana might have testified to in 1975.

But if that is what Sam Giancana was going to say,

that is an explosive issue.

If Sam Giancana really had something to do

with the assassination of JFK in collusion with the CIA,

that is information that the CIA does not want out,

and it is good reason to kill Sam Giancana.

Since he first became the head

of the Chicago Mob,

Sam Giancana has kept the Chicago Police Department

in his pocket,

but as he prepares to go on the witness stand in 1975,

this once-close relationship may have sealed his fate.

Since Giancana's set to testify

in front of a Senate committee,

federal prosecutors have a vested interest

in keeping him alive.

In fact, on the night of Giancana's murder,

there are two officers that are stationed

directly outside of his house.

At about 10:30 on the night of the shooting, they left.

The skeptics would argue

what they did was leave him unprotected.

It's really extraordinary

that, within about an hour or so after the cops leave,

they're called back by the housekeeper

saying that Sam Giancana has been murdered.

And then asked to investigate it,

the Chicago PD put it off to the local police department,

who don't have the experience

or the resources to find out who killed Sam Giancana.

So this brings up a lot of questions.

Why were they not there?

Why won't they investigate it?

There's people who believe that Chicago police

deliberately leave the case unsolved

because they have something to hide.

It's very possible when you consider

the history of the Chicago Police Department

that they played some role

in the conspiracy to get rid of Giancana.

The Chicago Police Department

is probably one of the most notoriously corrupt

organizations in the history of law enforcement.

Chicago police and their connection to the Mob

goes back all the way to the gangland days of the 1920s

and the 1930s, when Al Capone was in charge

and was able to pay off officers and to pay off judges

to make sure that they looked the other way

when crimes were being committed.

Now, it would be ludicrous to argue

that every Chicago policeman was corrupt.

But by the time of the Giancana murder,

reporters noted, there'd only been two gangland murderers

that had been solved.

Sam Giancana himself bragged to his associates

that he had many policemen in his back pocket.

An amazing character named Richard Cain

is the perfect example of this intermingling

between law enforcement and the Mafia in Chicago.

Richard Cain was a Chicago cop

who was a great police investigator,

and so they say, "Wow, he's a terrific cop.

But actually, secretly, he was on the payroll

of Sam Giancana and always had been.

His police training came in really handy for the Mob

because he would put mobsters through lie detector tests,

not to try and get them on a crime,

but to see if they were talking about the Outfit.

Cain winds up going to jail.

And what does he do when he gets out?

He goes straight to work for Sam Giancana again,

and he's Sam Giancana's driver for a couple years.

And then he shot in the face with a shotgun

inside of a sandwich shop.

But it wasn't just cops who were corrupt in Chicago.

Other parts of the justice system were on the take.

During the investigation,

there's a judge who is actively stonewalling

the progress of the police.

He refuses to allow police to investigate Giancana's desk.

When the police finally opened the desk drawers,

they find the guest list

at one of the weddings of Giancana's daughters.

And this judge was on the guest list.

So what we're looking at is

a law enforcement system in Chicago

that is consistently been corrupt

when they had to deal with organized crime.

Now, historians have researched this,

and there's really no hard evidence

tying the Chicago Police Department

with the death of Sam Giancana.

It is possible, though, that Chicago police feared

that Giancana would eventually spill the beans

about activities between police and the Mob.

And since he's no longer the main power broker,

there's no reason to be nice anymore.

And if that were the case,

Giancana may have ended up paying the ultimate price.

It's still considered an open homicide.

We don't know who killed him, but there were a lot of people

who wanted Sam Giancana dead.

This is a man who has infiltrated American business,

the CIA.

It's hard to imagine a mobster

more enmeshed with the United States government.

You can't help but wonder if we could just figure out

who killed Sam Giancana and why

it might help us solve some even larger mysteries.

It's the thread that you could pull,

and the next thing you know,

the whole ball of the yarn is gone.

50 years later, the unsolved murder of Sam Giancana

still raises as many questions as there are suspects.

It remains one of the most elusive

and intriguing murders in the annals of organized crime,

particularly for the secrets it may hold

about a truly tumultuous period in our history.

I'm Laurence Fishburne.

Thank you for watching History's Greatest Mysteries.