A Texas judge denied the motion by the conspiracy theorist Alex Jones to dismiss a defamation lawsuit brought against him and his Infowars operation by the parents of a Sandy Hook shooting victim, in a ruling released on Thursday.

The lawsuit was filed in state district court in Austin by Veronique De La Rosa and Leonard Pozner, parents of Noah Pozner, who was 6 years old when he was killed in the 2012 mass shooting at Sandy Hook Elementary School in Newtown, Conn.

On his radio broadcast and in videos, Mr. Jones for years spread bogus claims that the shooting was a “false flag,” an event staged by the government as part of an effort to confiscate Americans’ firearms, and that the parents of the children killed were “crisis actors.”

After Mr. Pozner succeeded in getting an Infowars video casting doubt on the shooting removed from YouTube, Mr. Jones showed his audience Mr. Pozner’s personal information and maps to addresses associated with his family, court documents say. Mr. Jones also falsely accused Ms. De La Rosa of participating in a faked interview with Anderson Cooper of CNN after the shooting, according to court documents.