Three men have been charged in the murder of a nightclub security guard who had been scheduled to testify in a gun case when he was shot dead in front of his Brookfield home — his court subpoena still in his pocket, his wife and 3-year-old son inside waiting to have lunch with him.

Comfort K. Robinson, 39; Jermaine E. Douglas, 25, and DeJuyon M. Johnican, 29, are all charged with first-degree murder in the death of 33-year-old Michael Smith in January, according to Brookfield police. At that time, Robinson had been facing charges in a 2015 criminal case that Smith was set to testify about.

“Michael Smith was a good man; a model citizen and hardworking family man who was killed in the prime of his life, just for doing his job,” police said in a statement.

Smith was killed in the 3700 block of Forest Avenue in Brookfield just after noon on Jan. 27, police said. His wife heard the gunshots, ran outside and called 911.

The court case he was supposed to testify resulted from an incident in the early morning hours of March 8, 2015. Smith was working a security detail at the now-shuttered Shrine nightclub at 2109 S. Wabash in Chicago, police said.

Robinson was involved in a disturbance at the club, and security intervened, police said. Robinson had a gun and was arrested by Chicago Police for several felonies, including being an armed habitual criminal and unlawful use of a weapon by a felon.

Smith was scheduled to testify as a witness in the court case against Robinson.

On the day of Smith’s murder, Robinson’s case was set for a bench trial. A motion was presented by his defense to have a jury trial instead, which was granted, delaying the start of the trial.

Smith left the courthouse and was followed home to Brookfield, police said. When he pulled up in front of his house, and before getting out of his car, Douglas pulled up and fired multiple shots at point-blank range.

Smith was struck several times and was taken to Loyola University Medical Center in Maywood, where he was pronounced dead at 12:46 p.m., authorities said.

Douglas took off in a blue vehicle, which was recovered by police the the next day.

Police said Johnican met up with Douglas and Robinson at different locations moments before and after the shooting.

Douglas, of the 7100 block of South Whipple, was arrested by Chicago Police on Nov. 15 after a chase ended in a crash at 87th and Ashland, police said. A loaded .50 caliber handgun was recovered after the crash.

Johnican, of the 1400 block of South 57th Avenue in Cicero, was arrested without incident near his home on Tuesday, police said.

Robinson, of the 2100 bock of South 13th Avenue in Broadview, has been in custody for several months on a separate felony charge, police said. He was arrested by Brookfield police and FBI agents upon his release from the Danville Correctional Center on Friday.

All three remain in custody at the Cook County Jail. Douglas was ordered held without bond, and Robinson and Johnican were each ordered held on $250,000.