Alex Murdaugh's Lawyer Says Real Killer Is 'Still at Large,' as Client Pleads Not Guilty to Murders

Maggie and Paul Murdaugh were shot at the family's estate in June 2021

Disgraced South Carolina attorney Alex Murdaugh has pleaded not guilty to all charges against him in connection with the deaths of his wife and son.

Murdaugh, 54, was charged last week with two counts of murder and two counts of possession of a weapon during the commission of a violent crime in connection to the June 2021 deaths of his wife, Margaret "Maggie" Murdaugh, 52, and their youngest son, Paul Murdaugh, 22.

When the judge asked for a plea, Murdaugh responded, "Not guilty."

Murdaugh's attorney, Dick Harpootlian, requested a speedy trial to begin as early as October. Harpootlian told the judge that Murdaugh wants the trial to begin as soon as possible because he believes that his wife and son's "killer or killers are still at large."

Authorities divulged no new details that would link Murdaugh to the killings, but prosecutor Creighton Waters said that the evidence against Murdaugh is "substantial."

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"Much of the information that has been gathered in the state grand jury case — all of the 81 allegations of white collar fraud and other crimes, drugs and the like — that has been gathered against Mr. Murdaugh over the course of that long investigation," Waters told the judge. "And a lot of that provides the background and the motive for what happened on June 7, 2021."

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Alex Murdaugh. Orange County Department of Corrections

On that night, Murdaugh called 911, saying he had come home and found Maggie and Paul gunned down on their 1,770-acre estate in the small town of Islandton, S.C. The mother and son had been shot with two different guns and were found outside the home, near the dog kennels.

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Long before he was charged in connection with the killings, Murdaugh was named as a person of interest in the case.

Murdaugh faces 81 other charges unrelated to the killings. Most of the charges are for alleged financial crimes, including misappropriating money from his law firm, defrauding clients of funds and computer crimes. Authorities allege that he also defrauded the family of his former housekeeper of a $4.3 million insurance settlement after she died in a mysterious slip-and-fall accident at his home.

Maggie, Paul and Alex Murdaugh.

After the deaths of his wife and son, Murdaugh made news again when he allegedly tried to stage his own death so that his one surviving son, Buster Murdaugh, 26, could benefit from a $10 million life insurance settlement. He was criminally charged in connection with the alleged botched suicide-for-hire plot and is awaiting trial in that case.

According to prosecutors, he had his associate Curtis "Eddie" Smith shoot him on the side of the road, but the shooting was unsuccessful and Murdaugh suffered only superficial wounds. Smith has pleaded not guilty in connection with that case.

Suspended from practicing law, Murdaugh has pleaded not guilty to all charges filed against him so far. He is jailed with no bond. His attorneys did not immediately return PEOPLE's calls for comment.