Was U.S. Supreme Court Justice Antonin Scalia murdered?

The question was raised point-blank by nationally syndicated talk-radio host Michael Savage and other people who smelt something fishy concerning the circumstances and aftermath of the death of the outspoken leader of the Supreme Court's conservative bloc.

Scalia, whom many consider as the conscience of the court, was the biggest hindrance to some of President Barack Obama's controversial executive programmes including Obamacare and new greenhouse gas emission restrictions.

In fact, Scalia played a key role in the Supreme Court's Feb. 9 decision that temporarily blocked the Obama administration from imposing its new rules to limit greenhouse gas emissions from power plants, Savage said.

"Just five, six days before Scalia was found dead with a pillow over his face, he was the lead voice against Obama's attempts to railroad that green gangsterism down our throats, he knocked it out? He was the one who did it," the talk radio icon said, according to WND.

Adding fuel to one of the conspiracy theories, commentator Paul Joseph Watson cited a report saying that Obama, when told of Scalia's death hours before the public announcement, was "thrilled" to be "relevant once again."

"If accurate, the report will feed suspicions that foul play may have been involved," he wrote.

Meanwhile, Joe Pappalardo of the Dallas Observer reported rumours that Scalia was either gassed or smothered or poisoned, according to WND.

"Scalia was not a young man. He was 79 years old and friends at the West Texas ranch where he died say he went to bed early because he didn't feel well," he wrote. "There are many natural causes of death that could be responsible. A heart attack seems to be the most probable cause, and local media are reporting that his death certificate will read 'myocardial infarction.' Other media reports say the cause will be deemed natural. Either way, no official is suggesting homicide."

Pappalardo said the report that a pillow was found over Scalia's head raises a number of questions.

"So could someone have entered his room and used that pillow to asphyxiate him? This method only really works with really old or young people, or those already unconscious. There are usually telltale signs of these murders — not only will most victims struggle, leaving signs of the fight behind, but the suffocation takes up to 5 minutes and the body shows this with haemorrhages under the skin. But there's a catch: Sometimes the suffocation triggers a heart attack, leaving the corpse without many of the signs of a homicide," he wrote.

But Pappalardo said there is "a good way to kill people without getting caught," which is poisoning.

He cited a muscle relaxant called succinylcholine which when injected into patients paralyses them so they can't breathe. "Most autopsies show this as a heart attack," he said.

Gassing also could have been used, he wrote, although it's less likely since there would be telltale signs.

The blog Heavy.com posed key questions on Scalia's death that remain unanswered.

First, why was there a pillow found over his head?

Second, why was Scalia's cause of death decided over the phone?

Third, why was there no autopsy?

Fourth, how come officials determined the cause of death so quickly?

The blog cited a suggestion that Obama was behind the death.

"The theory is that Obama had Scalia killed so that he could fill his Supreme Court seat before he leaves office, though it appears it will not be easy for him to do that as the GOP-controlled House and Senate seem prepared to challenge any nomination," the blog said.

Another theory was that the Bush family was behind the death because of something Scalia knew about them regarding the Sept. 11, 2001 terrorist attacks on the U.S.