The lead investigator in the 2009 shooting death of Baton Rouge rapper Chris “Nussie’’ Jackson testified Wednesday that Michael Louding, the man accused in the killing, appeared to be “stalking’’ Jackson the night of the slaying.

John Dauthier, a detective in the Baton Rouge Police Department’s homicide division, said the video surveillance system from a Shell gas station at North 27th and Florida streets shows Jackson, a group of his friends and Louding in the store between 10:50 p.m. and 11:10 p.m. on Feb. 9, 2009.

Dauthier said the person he believed to be Louding appeared to be “stalking’’ or “closely observing’’ Jackson in the store.

Officers responding to a reported shooting that night found a man shot in the 2500 block of North Boulevard at 11:24 p.m., police have said. The man directed police to 2317 America St., where they found Jackson dead inside, police said.

Dauthier’s testimony came during a hearing on a defense motion to suppress Louding’s statements to police.

In those statements, portions of which were played in court last week, Louding confesses to killing Jackson.

If state District Judge Don Johnson grants the defense motion, prosecutors could not use Louding’s videotaped statements at his first-degree murder trial.

Johnson said at the conclusion of Wednesday’s hearing that he will issue a ruling Aug. 8.

The judge gave little indication of how he will rule, but did say there is no indication that Louding “lacks capacity.’’

Johnson also said it would have been preferable to have everything Louding told police on tape.

Louding’s court-appointed attorney, Margaret Lagattuta, argued Wednesday that about eight hours elapsed from the time police first began talking with Louding on May 14, 2010, and when they started to videotape their conversation.

“My problem is the void, the eight-hour void,’’ she told the judge.

Lagattuta suggested Louding, 18, “misunderstood’’ the purpose of his police interviews. He was 17 at the time of the interviews, and 16 when Jackson was killed.

“Mr. Louding in his youth and inexperience thought he was going to be a witness,’’ Lagattuta argued.

Prosecutor Dana Cummings countered that Louding “clearly understood what was going on.’’

“He was advised ?this will be used against him in a court of law.’ How else can you interpret that?’’ Cummings asked.

The prosecutor pointed to Louding’s calm demeanor during the interviews and said, “It’s very clear he wants to cooperate, for whatever reason.’’

Louding, whose nickname is “Marlo Mike,’’ is accused in the slayings of six people over a 14-month period, beginning with Jackson’s killing.

Louding is charged with five counts of first-degree murder; one count of second-degree murder; and two counts of attempted first-degree murder.

Nationally acclaimed Baton Rouge rapper Torrence “Lil Boosie’’ Hatch also is charged with first-degree murder in one of those killings, the Oct. 21, 2009, shooting death of Terry Boyd.

Prosecutors allege Hatch hired Louding to kill Boyd.

Louding is not eligible for the death penalty because of his age at the time of the killings.

Prosecutors have not decided whether to seek the death penalty against Hatch.