NEW YORK — For six minutes, Jordan Neely was pinned to a subway floor in a chokehold that ended with him lying still. But that’s not what killed him, a forensic pathologist testified Thursday in defense of the military-trained commuter charged with killing Neely.

A New York City medical examiner determined that Daniel Penny’s chokehold killed Neely, an agitated, mentally ill man whom Penny and some other riders found threatening.

But the defense’s pathologist, Dr. Satish Chundru, told jurors that Neely’s medical records and bystander video didn’t show telltale signs of known types of fatal chokeholds.

Among the discrepancies, he said: the location and extent of bruising on Neely’s neck, and the small amount of petechiae — small red spots caused by subsurface bleeding — on his eyelids.

“In your opinion, did Mr. Penny choke Mr. Neely to death?” defense lawyer Steven Raiser asked.

“No,” replied Chundru, who has worked as a medical examiner for county governments in Florida and Texas.

He said Neely died from “the combined effects” of synthetic marijuana, schizophrenia, his struggle and restraint, and a blood condition that can lead to fatal complications during exertion.

“The chokehold did not cause death,” the pathologist said.

Penny, 26, has pleaded not guilty to manslaughter and criminally negligent homicide. His defense says the Marine veteran and architecture student was defending himself and a car full of subway riders.