An ex-preacher allegedly admitted to killing an 8-year-old Delco girl in 1975. His lawyer says his confession was coerced

At the start of his four-hour interview with two Pennsylvania State Police troopers in July, David Zandstra demonstrated a keen memory of his life, Cpl. Andrew Martin said Wednesday.

That memory, prosecutors said, would provide a confession and answer to the mystery of an 8-year-old girl who walked out of a Sunday school classroom and into history as a victim of one of the most confounding cold-case murders in Delaware County. But Zandstra’s attorney is now seeking to prevent a jury from hearing that confession, saying it was elicited under duress.

In that interview with police, Zandstra was able to recall decades of his personal history: the churches he preached at as a Christian minister and the towns he lived in while doing so. At one point, the 84-year-old even corrected Martin about a detail he had gotten wrong, the detective said Wednesday during a pretrial hearing at the Delaware County courthouse.

But when Martin and his partner began to press Zandstra about the death of Gretchen Harrington, he said his mental faculties were in decline. Gretchen, an 8-year-old Broomall girl, was found dead in 1975 months after last being seen walking to the church Zandstra oversaw.

“My brain is 83 years old, and you’re throwing a lot of stuff at me,” Zandstra said in the interview. “You’re asking me a lot of questions I’m unsure of.”

By the end of the interview, Zandstra admitted to driving Gretchen to a secluded section of Ridley Creek State Park and ordering her to undress “to have some sort of sexual pleasure,” according to a video recording of the confession played publicly for the first time during Wednesday’s hearing.

He said he bludgeoned her in the head with a rock and covered her body in tree branches. Afterward, Zandstra kept his actions a secret while assisting with the search for Gretchen and presiding over her funeral.

Zandstra has been charged with first-degree murder, kidnapping and related crimes in Gretchen’s death. His attorney, Mark Much, is now seeking to have the confession suppressed at trial.

Much asserted during Wednesday’s proceeding that Martin coerced and misled Zandstra, telling him the interview was informal and that he was not in any trouble. In reality, Much said, Martin had identified him as a suspect in the case and spoke to him alone, despite a request from Zandstra’s wife for the couple to be interviewed together due to his health issues, including what Much described as “vascular dementia.”

Martin also lied to Zandstra, Much said, telling him that they had an eyewitness account of Gretchen getting into Zandstra’s car before her disappearance, and that they had found her DNA on rocks taken from the site where her body had been found.

Deputy District Attorney Geoff Paine disputed that theory of the case. Martin and his partner had flown to Georgia to meet with Zandstra and his wife at their convenience. The couple had agree to meet, he said, and Zandstra was always free to leave or suspend the interview at any point.

The two troopers’ primary purpose in sitting down with the former preacher was to get a swab of his DNA, to compare it with evidence they had as they continued to investigate the case.

The two came without weapons or handcuffs, and were so caught off-guard by Zandstra’s confession that Martin had to scramble to borrow a computer from a local police officer in Georgia to start drafting the affidavit of probable cause for the former preacher’s arrest, Paine said during Wednesday’s hearing.

Delaware County Court Judge Anthony Scanlon said he will issue a ruling on Much’s motion to suppress Zandstra’s confession in the coming weeks.

Zandstra became a suspect in Gretchen’s death in January 2023, when a woman who was friends with one of Zandstra’s daughters met with Martin, telling him she had been molested by Zandstra during a sleepover at his home a week before Gretchen disappeared.

When Martin asked him about this during their interview months later, Zandstra said that he had at one point sought confession and absolution for “sexually touching a child,” confirming the woman’s story.