Nils Peterson

Nils Peterson, a lieutenant detective with the Newton Police Department, led the local investigation into Ben Rifkin’s murder before the State Police CPAC unit assumed control. His testimony, initially intended to establish routine facts about the crime scene and the investigation’s timetable, becomes consequential when it places Andrew Barber’s role and Peterson’s own investigative judgment before the jury.

Identity and Background

Peterson had joined the Newton force a few years before Andrew Barber began working at the district attorney’s office. Barber says he had known Peterson since 1984. By the time he testified, Peterson was in his early fifties; Barber recalls that his appearance had changed over the years, while his manner on the stand remained soft-spoken. In Barber’s assessment, juries responded well to him.

Role in the Investigation

Peterson headed the Newton department’s initial investigation after the body was discovered. Neal Logiudice called him as a foundational witness, following the usual sequence of establishing the first day’s essential facts before moving on to the later State Police investigation. Peterson described the discovery scene and the early search of Cold Spring Park: the body had been turned onto its back by the jogger who found it, and investigators searched the park after sealing it off but found no evidence that resolved the case. Several footprints were located, though none near the body could be matched to a suspect; as a public park, the area could contain many unrelated traces.

Testimony and Its Consequences

Peterson’s appearance became important beyond that procedural groundwork. Asked who had been assigned to the case as assistant district attorney, he answered that it was Andrew Barber, who was then in the courtroom beside the defendant. The testimony made Barber’s earlier involvement visible to the jury and gave the defense grounds to explore his decisions as an investigator. The judge allowed that inquiry because Logiudice had opened the subject.

On cross-examination, Peterson said he had not disagreed with Barber’s investigative decisions. He also confirmed that, at the beginning of the investigation, he had wanted to pursue Leonard Patz. The exchange connected the local detective’s early investigative judgment with the defense’s effort to examine why that lead had not remained central to the case.

Narrative Role

Peterson is presented mainly through the trial testimony and Barber’s recollections rather than through an independent account of his private life. His calm courtroom presence gives weight to the practical details of the initial investigation, while his answers expose the history behind the prosecution’s apparently routine witness sequence. The testimony shows that the case’s early direction had involved both Barber and interest in Patz, complicating any simple division between the local investigation and the later prosecution.