A 28-year-old New Haven man who was acquitted of murder and conspiracy charges related to a 2007 shooting in downtown New London has scored a second legal victory in local courts.

In his latest arrest, a drug case, Curtis McGill will not be prosecuted because the arresting officer, Roger Newton, resigned from the New London Police Department in February after he was accused of planting drugs on a local resident.

In the April 2011 drug arrest, New London police said they seized more than 3 ounces of crack cocaine and about 18 grams of Illy, or PCP.

Superior Court prosecutor Stephen M. Carney said little on the record during McGill’s court appearance Wednesday and declined to comment later on why he “nolled” the drug case.

McGill has been free on an $85,000 bond and has appeared in New London Superior Court 18 times while his drug case was pending. After the state announced he would not be prosecuted, he quickly left the courtroom with his attorney, Peter E. Scillieri.

Scillieri said the state’s drug case against McGill had relied heavily on Newton.

“Everything that unfolds from the initial stop essentially rests on the shoulders of Officer Newton,” Scillieri said. “I can’t get inside the state’s attorney’s head. From our side, all I can say for sure is that it’s evident the state couldn’t go forward and meet their burden on the search issue. My speculation would be that it’s because Officer Newton wouldn’t be available.”

The 27-year-old police officer resigned in February as his superiors and state officials investigated an allegation that he had planted drugs on Lance Goode in October 2010.

In the McGill case, Newton wrote in an incident report that he spotted McGill’s “suspicious vehicle” at 1:57 a.m. on April 13, 2011, as McGill sat in his Ford Taurus on Shaw Street. Newton reported that he watched McGill exit the car, stand on the street and then re-enter the car. Newton said the neighborhood was quiet and it “appeared very suspicious to me what this male might be doing in this location at this time of morning.”

Newton wrote that he pulled up behind McGill’s car and turned on his spotlight but didn’t activate his emergency lights. He approached McGill, who told him he was looking for a friend’s house. While he was speaking to McGill, a dispatcher notified him that McGill’s license was suspended.

Newton said he asked McGill to step out of the car, then noticed the strong odor of PCP, which he said smells like permanent markers.

Two other officers arrived on the scene, and Newton searched McGill and his car using his police dog, Kilo. The dog alerted Newton to drugs in the car and in the area of McGill’s buttocks.

The drugs were seized from the car. Though McGill was strip-searched after he was placed under arrest, nothing was found, Newton wrote. McGill told police he had “pushed the object inside of him and that he would wait us out till he had to take it out of him,” the report said.

In October 2008, a jury acquitted McGill of conspiring to kill Vernell O. Marshall in downtown New London the previous year. McGill was not the alleged gunman, but the state had contended that he had a “beef” with Marshall involving a payment for PCP and ordered two associates, Kurtis Turner and Jonathan Fuller, to shoot him.

Turner, the shooter, was convicted and sentenced in July 2009 to 60 years in prison. Fuller was not prosecuted.

McGill’s drug case was being heard at the so-called “Part A” court on Huntington Street, where major crimes are tried, but many drug cases are prosecuted at the lower-level court, known as G.A. 10, on Broad Street.

Michael E. Kennedy, supervising prosecutor at G.A. 10, said drug cases in which Newton was involved are getting extra scrutiny.

“Less than half a dozen have come to my attention,” Kennedy said. “Some of those have been nolled (not prosecuted) and some have not. Just because Officer Newton investigated or was involved in the investigation of a case doesn’t automatically cause the case to be nolled.”

Jennifer Nowak, a public defender at G.A. 10, also said the cases involving Newton are being taken “on a case-by-case basis.”

k.florin@theday.com