The parents of a child killed in the 2012 Sandy Hook Elementary school shooting described being put through a “living hell” caused by conspiracy theorist Alex Jones using his media platforms to push claims it was a hoax.

The parents led a day of charged testimony on Tuesday that included the judge scolding the bombastic Jones for not being truthful with some of what he said under oath.

Neil Heslin and Scarlett Lewis, whose son Jesse, 6, was killed at Sandy Hook, took the witness stand on the final day of testimony in the defamation damages trial against the Infowars host and his media company Free Speech Systems.

They are seeking at least $US150 million ($216 million) damages.

In a gripping exchange, Ms Lewis spoke directly to Jones.

“I am a mother first and foremost and I know you are a father. My son existed,” she said.

“I am not deep state … I know you know that … And yet you’re going to leave this courthouse and say it again on your show.”

At one point, Ms Lewis asked Jones: “Do you think I’m an actor?”

“No, I don’t think you’re an actor,” Jones responded before the judge admonished him to be quiet until called to testify.

Ms Lewis continued trying to impress on Jones that the Sandy Hook shooting and trauma inflicted in the decade since then was real.

“It seems so incredible to me that we have to do this – that we have to implore you, to punish you – to get you to stop lying,” she said.

Mr Heslin and Ms Lewis are among several Sandy Hook families who have filed several lawsuits alleging that Sandy Hook hoax claims pushed by Jones have led to years of abuse by Jones and his followers.

Mr Heslin and Ms Lewis said they feared for their lives and had been confronted by strangers at home and on the street.

Ms Heslin said his home and car had been shot at. The jury heard a death threat sent via telephone message to another Sandy Hook family.

“I can’t even describe the last nine-and-a-half years, the living hell that I and others have had to endure because of the recklessness and negligence of Alex Jones,” Mr Heslin said.

Jones later took the stand himself, testified that he had long wanted to apologise to the plaintiffs.

“I never intentionally tried to hurt you. I never said your name until this came to court,” Jones said.

“The internet had questions, I had questions.”

The judge later scolded Jones for telling the jury he complied with pre-trial evidence gathering even though he did not, and that he was bankrupt, which has not been determined.

“This is not your show,” Judge Maya Guerra Gamble told Jones.

“Your beliefs do not make something true. You are under oath.”

The defamation suit is one of several brought by families of victims who say Jones’s followers harassed them as a result of his false claims.

– AAP