Cyril Williams (Prince George’s County Police Department)

A Seat Pleasant man who prosecutors say gunned down a Maryland state trooper to get revenge after the trooper threw him out of a restaurant was convicted Friday of first-degree murder and other related counts.

Jurors deliberated for about three hours before handing down the guilty verdicts against Cyril Williams, the man accused of shooting Maryland State Trooper Wesley Brown outside a Forestville Applebee’s in June 2010. Law enforcement officials and family members who had packed a Prince George’s County Circuit Court room to watch Williams’s trial this week let out a hushed “Yes!” as the verdict was read.

“This is what we prayed for,” said Janet Brown, the victim’s sister. “We’re happy that justice was served.”

Supporters of Williams, 29, left the courtroom hurriedly, shouting, “Hold your head up, dog!” as sheriff’s deputies led him away.

From the start, the trial was emotional. Brown was a beloved trooper who had started a youth mentoring group in Seat Pleasant, and prosecutors accused Williams of callously ambushing him while he was working an off-duty security job. Brown, prosecutors said, had thrown Williams out of the Applebee’s on Donnell Drive for being drunk and disorderly. They said Williams left to get a gun, drove back and opened fire on the restaurant’s door when Brown stepped outside to talk on the phone.

“Hid behind a tree like the big man he was,” Assistant State’s Attorney Carol Coderre told jurors in her closing statement. “Fired each and every single bullet that the gun was capable of holding at Wesley Brown.”

Defense lawyers had argued that there was not enough evidence to connect Williams to the shooting. Although one witness identified him as the shooter in court, she could not do so definitively in the past, said William Mitchell, an attorney for Williams. Other witnesses, Mitchell said, had provided only broad descriptions that matched Williams; prosecutors presented no DNA or fingerprint evidence.

“You don’t convict on probablys, maybes and I suspects,” Mitchell said.

But even if the prosecutors’ case wasn’t flawless, it was strong. Cellphone records showed Williams moving roughly from Applebee’s to an area where he retrieved the gun, then back to Applebee’s about the time of the killing. Anthony Milton, who has admitted giving Williams the gun and has pleaded guilty to being an accessory after the fact, testified that he drove with Williams to the restaurant and saw him shoot at the door.

And in the months after the incident, jailhouse informants and other witnesses testified, Williams bragged about killing a police officer and tried to intimidate an officer transporting him and another inmate, who planned to testify against him.

Brown, prosecutors said, was quite the opposite of his shooter — a community and family-oriented police officer who believed in second chances. Prosecutors said Brown let Williams go after Williams took a swing at another officer that night in June — even though the officer wanted to arrest Williams.

In her closing argument, Coderre urged jurors not to make the same decision.

“Don’t let him go,” Coderre said. “Just don’t let him go.”

Williams is scheduled to be sentenced May 10. Prince George’s State’s Attorney Angela D. Alsobrooks said prosecutors intend to ask that Williams serve life in prison without parole, noting the senseless motive that precipitated the crime.

“It’s a complete waste,” Alsobrooks said. “It’s a tragedy of just horrific proportions.”

William Brennan, another of Williams’s attorneys, declined to comment after the verdict.