Between the white church and the yacht club, the Barrington River was calm, the sun was shining, and three Barrington High School boys were concluding a summer day of motorboating and kneeboarding when the pivotal moment in their lives began and ended in a matter of seconds.

The moment began with Ryan A. Greenberg at the wheel of a 20 1/2-foot-long motorboat, Brendan W. Loflin standing in the stern, and Patrick Murphy in the water, dangling from a kneeboard — a short surfboard ridden in a kneeling stance.

Greenberg and Murphy, both 17, were involved in “a verbal exchange with references to Greenberg’s inability to operate the boat properly and Murphy’s inability to properly ride on the kneeboard,” according to a reconstruction by a state environmental police officer.

Greenberg “throttled up” and pointed the boat at Murphy, the reconstruction report says. With the boat under “increased throttle,” Greenberg then made a hard right turn, causing the boat to dip or “heel” to the right (starboard), the report says.

“With the boat heeled to starboard, this aligned Murphy’s head with the oncoming propeller,” the report says. “The entire maneuver likely would have been completed in a matter of seconds, leaving Murphy with no chance to swim or dive to safety.”

Authorities have released few details of the events that led to Murphy’s death in July 2007. But more than a year later, prosecutors are preparing to try Greenberg in an adult court on charges that include second-degree murder. And a recent Family Court hearing has brought to light the reconstruction report, which provides the public with the most detailed account to date of what happened on the river that day.

The Journal obtained the report, titled “Reconstruction of Barrington River Fatality,” from Family Court files after Greenberg’s defense lawyers entered the document as an exhibit during a hearing in late July. As a result of the hearing, Greenberg was waived out of Family Court into Superior Court.

During the hearing, Loflin contradicted some of his initial statements, which were cited in the reconstruction report. The day after Murphy’s death, Loflin had told authorities that Greenberg “was screwing around like he was going toward him and then he turned away.” But during the July hearing, Loflin said Greenberg did not try to turn the boat away at the last second.

During the hearing, defense lawyers indicated they might call as a witness environmental police officer Daniel K. White, who did the reconstruction. They decided against bringing White to the stand, but after introducing the report, the lawyers challenged some key conclusions.

For example, defense lawyer William P. Devereaux challenged the idea that Greenberg and Murphy were angry at each other that day, saying it was not uncommon for the “school chums” to engage in harmless “trash talk” and to use “salty language.”

THE DOCUMENT depicts July 17, 2007, as a serene summer day with temperatures in the 80s and little wind. It says the “incident” occurred on the Barrington River north of the County Road Bridge and south of the Massasoit Avenue Bridge, also known as the white church bridge. The area is often used for water-skiing and towing people behind boats on kneeboards or inner tubes.

Greenberg, Murphy and Loflin were in a 2007 center-console Sailfish powered by a 200-horsepower Yamaha outboard motor. The boat was registered to Andrew W. Davis, of Barrington. His son, Turner Davis, had gone aboard another boat, but it wasn’t unusual for Greenberg to operate the boat, according to the report.

So with Greenberg at the wheel and Loflin aboard, the boat began pulling Murphy, who was lying on the kneeboard, holding a tow line. Murphy, who was not wearing a life jacket, kept falling off the kneeboard, the report says.

The report says there’s evidence Greenberg drank alcohol that day, and a preliminary medical examiner’s report indicated Murphy had alcohol in his system.

“In the minutes approaching 7:30 p.m., the events of the day culminated with the 21-foot Sailfish at a stop with Murphy in the water positioned off the bow and slightly to port,” the report says. “Greenberg was at the helm of the Sailfish and Loflin was standing in the stern area in the starboard corner of the deck. Loflin was able to see Murphy from his position.”

Murphy was holding onto the kneeboard, probably with his legs dangling in the water, the report says. As the “verbal exchange” between Murphy and Greenberg “became heated, Greenberg engaged forward gear and throttled up,” the report says.

Greenberg turned the boat slightly to the left (port), so the boat was pointing at Murphy, the report says.

While “under the increased throttle,” Greenberg then made a “hard right turn,” according to the report and its diagrams. That maneuver would cause the boat to tilt or “heel” to the right (starboard), the report says. And a diagram indicates that would push the rear of the boat to the left (port).

“This is when the kneeboard would have contacted the hull,” the report says, describing a “bluish/purple” scuff mark along the port side of the hull. “Murphy would have been struck by the propeller as the Sailfish passed over him.”

Based on where the kneeboard scuffed the hull, the boat “likely attained a speed at or near planing speed,” the report says. (A “planing” boat skims across the water rather than pushing through it.) “This indicates that the Sailfish was close to a planing attitude rather than a slower, bow high, attitude.”

Also, the report says, “this better explains the 4-inch spacing of the two propeller wounds to Murphy’s head. This 4-inch spacing is more consistent with a speed closer to or approaching planing speed, rather than a slower plowing speed such as a boat just starting from a stop.”

Loflin saw Murphy appear from under the back of the boat, face down in the water, the report says. “Loflin also states that he thinks he observed blood in the water,” the report says.

After Murphy’s body sank beneath the surface, Greenberg and Loflin operated the Sailfish in the area, searching for him and “possibly striking the body again, creating the four propeller bruises on back of left thigh,” the report says. “These wounds are consistent with a slow, idling speed.”

Greenberg and Loflin then took the boat up the river to an area referred to as Ski Beach, where a 2006 Mastercraft ski boat was being operated by John Lyons Jr., according to the report. Both boats returned to search for Murphy, and the Mastercraft “struck the body, causing severe trauma to the left calf and left elbow of Murphy,” the report says. “Since the vessel is very heavy and the engine quite powerful, it could have gone unnoticed by the operator.”

RICHARD SNYDER, a “propeller expert” who teaches at the Advanced Boat Accident School, concluded the head wounds were caused by a propeller that turned clockwise, and severe leg injuries were caused by a propeller that turned counterclockwise. The report concludes that the Sailfish propeller struck Murphy in the head, causing his death, and that the Mastercraft caused leg injuries “well after Murphy received the initial fatal head injuries.”

The report also says “contributing factors to this incident are: reckless operation of the Sailfish by Ryan Greenberg, alcohol use, and anger stemming from a verbal confrontation.”

During the Family Court hearing, defense lawyers challenged those conclusions, and they challenged the notion that the boat was at or near planing speed when it reached Murphy.

The report describes how in January 2008, environmental police officers conducted a test run and found the boat reached planing speed after traveling 70 to 80 feet in 3 to 4 seconds. “The measurements are consistent with what is being provided by witnesses, investigators and physical evidence,” the report says.

But Devereux, the lead defense lawyer, said the measurements actually contradict testimony from Loflin, who said the boat was about 20 feet away from Murphy before Greenberg hit the throttle.

Devereaux suggested that the front (bow) of the boat rose up, causing both Greenberg and Loflin to lose sight of Murphy. He said that when Greenberg turned to the right (starboard) to avoid Murphy, the back of the boat slid to the left (port), and the propeller hit Murphy.

DURING THE HEARING, another defense lawyer, former Gov. Philip W. Noel, asked Family Court Chief Judge Jeremiah S. Jeremiah Jr. to give the defense time to have its own expert put the Sailfish in the water “and test it for performance characteristics.” But a prosecutor said the state was not relying on experts or the report in establishing probable cause. Jeremiah rejected Noel’s request.

Noel, who has been familiar with boats for 65 years, said the defense wanted to “reconstruct a much more accurate depiction of how the alleged accident took place.” And he called the indictment on a second-degree murder charge “a travesty.”

Greenberg, now 18, has been indicted on charges of second-degree murder, reckless boating with death resulting, underage possession of alcohol and refusal to submit to a chemical test. He has pleaded not guilty. A status conference on the case is scheduled for Sept. 19 before Superior Court Judge Daniel A. Procaccini.

efitzpat@projo.com