A worker at Suburban Hospital in Bethesda was convicted Wednesday of first-degree murder for sneaking into a basement boiler room on New Year’s Day and stabbing his boss 72 times with a 12-inch knife, leaving it lodged in the victim’s neck.

Jurors deliberated for much of the day in a case that was closely watched because five years ago in the District, the defendant, Keith Little, 50, was acquitted on charges that he fatally shot a co-worker six times.

“If he would have gone free, who would have been his next victim?” Roosevelt Brockington Sr., the father of the Suburban Hospital victim, said.

Roosevelt Brockington Jr. of Lusby was the lead engineer in the hospital’s boiler room, hidden far from the public’s view in the basement. Prosecutors put together a circumstantial case, based in part on how few people had access to Brockington’s office.

During a Montgomery Circuit Court trial, prosecutors pounded away at Little’s motive, saying that he hated his boss and that Brockington had given Little a poor review. Four days after the killing, they said, Little furtively tried to clean a glove that had his and the victim’s DNA on it.

Brockington’s father sat through the trial with his wife, daughter and Sallie A. Bruce, pastor of St. John Church of God in the District. Bruce, 72, who uses a wheelchair after suffering a stroke, still preaches.

“My number one deacon,” she said of Brockington. “He did everything I asked him to do.”

Bruce said she thinks Brockington, 40, didn’t feel all of the many wounds inflicted. “I don’t think God allowed that,” she said.

Prosecutors said that on the morning of Jan. 1, Brockington was in his office and on the phone with a friend, who heard a voice say, “Give me your money.” Brockington said, “That’s all I got” and pleaded with the man not to hurt him. There were screams, and the phone went silent.

Detectives arrived to find Brockington repeatedly stabbed, a crime they said indicated personal anger, not robbery.

Detectives had reason to focus on a limited pool of suspects, given the seclusion of the boiler room. They also learned of Little’s prior murder case and questioned him twice, on Jan. 1 and Jan. 5, taking a DNA sample the second time. Less than 60 minutes after the second interview, after the detectives left, Little made a series of maneuvers that help lead to his undoing.

He poured scalding, chemically treated water into a bucket. A co-worker walked over to check it out and saw gloves and a black ski mask inside the bucket. Little approached quickly, said “I’ll take care of that,” and ultimately stuffed the gloves and ski mask into the bottom of a trash can. That act was caught on a surveillance camera, played for jurors.

“That was very critical,” prosecutor George Simms said. “That is demonstrable evidence of him doing what we argued he did: conceal critical evidence.”

Forensic examiners tested the glove. Little’s DNA was found on the inside, and the victim’s DNA was found on the outside. A variety of tests for blood yielded both positive and negative results and were tossed out of the case. But prosecutor Robert Hill was permitted to argue that he believed a brown spot on the outside of the glove was Brockington’s blood.

“This is a dangerous man,” said Montgomery County State’s Attorney John McCarthy. “He is going to finally be held accountable for taking a human being’s life.”