A new court document charging suspected Long Island serial killer Rex Heuermann with two additional murders says that investigators found a deleted “planning document” on one of his electronic devices detailing his “self-education and ‘homework’ on the topic of carrying out serial, sexual murder.”
Heuermann appeared in court Thursday morning on charges that he killed Jessica Taylor in 2003 and Sandra Costilla in 1993, bringing to six the number of women the 60 year old Manhattan architect is charged with killing.
739871993 Rex Heuermann Superseding Bail Application From June 6 2024 by kc wildmoon on Scribd
He was previously charged with the deaths of Amber Costello, Maureen Brainard-Barnes, Megan Waterman, and Melissa Barthelemy, whose bodies were found in close proximity along a desolate stretch of Gilgo Beach in 2010.
Some of Taylor’s remains were found in the same general area in 2011, but she was dismembered and her torso was found near Manorville in 2003. The documents say a match to Heuermann could not be excluded from hairs found on or near both Taylor’s and Costilla’s bodies and that a female hair found on Costilla’s body could not be excluded from a woman who lived at Heuermann’s Massapequa Park home but moved out in September 1993.
In searches of electronic devices seized from Heuermann’s home, investigators said they uncovered his “significant collection of violent, bondage, and torture pornography, currently dating back to 1994” and perhaps most importantly, the “planning document,” which appeared to have been relegated to a space on the device where deleted documents remain.

The document noted Heuermann’s concerns about being seen on video surveillance, leaving forensic evidence behind, what supplies he needed to buy, how to prepare a body to take to “dump sites,” and remembering not to charge gas or leave any other kind of paper trail.
The document lists booties, “lie” or acid, a police scanner, rope, hair nets, drain cleaner, and other items as supplies. It reminds to “recon dumster [sic] locations” for “next time,” and mentions the name “Megan.”
“The more you do the more clues you give,” says the document, which also lists where surveillance cameras were found on various roads on Long Island.
Thursday’s arraignment follows a series of new searches on Long Island, including a return to Heuermann’s Massapequa Park home, earlier this year, as CrimeOnline reported. Heuermann has pleaded not guilty to the murders of the so-called Gilgo 4.
Costilla’s murder had long been connected with another serial killer, John Bittrolff, who was eventually convicted in two other murders and is serving 50 years to life in prison, but investigators were never able to firmly tie Bittrolff with Costilla.
Unlike all the other victims tied to Heuermann, including Taylor, Costilla was never described as a sex worker.
Heuermann remains in jail without bond.
Authorities have scheduled a news conference on the matters for later Thursday morning.
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[Featured image: Sandra Costilla/Suffolk County Police Department and Jessica Taylor/John Ray Law via AP. Inset: Rex Heuermann/Suffolk County Sheriff’s Office via AP]