Our story begins one evening six years ago, when Omar Sullivan opened an envelope from Essex County authorities and slowly read the document inside with rising terror.

He’d had his share of parking tickets and moving violations, but this notice was ordering him to court to answer gun and drug charges. He was so surprised and shaken that he didn’t even finish reading. What gun? What charges?

“I was so damned scared,’’ he said.

Sullivan, then living in Union Township, hustled on down to the courthouse in Newark and found out he was being charged with a series of crimes that had nothing to do with him: possession of a .22-caliber gun, heroin, steroids and 27 vials of cocaine near a school.

When Sullivan checked in at the courthouse and told his story, the sheriff’s department took his fingerprints and soon found they did not match those of the defendant they were seeking. Some guy named Steven Sylvester was apparently using his name, Social Security number, date of birth, information he may have gotten when Sullivan lost his wallet in 2006. So when Sylvester was arrested the authorities thought he was Omar.

The courts acknowledged a grievous error had been made and soon cleared everything up, or so Omar Sullivan thought. Kim Branch, a court service supervisor, gave him a letter explaining the gun and drug charges belonged to Sylvester.

“I thought that was it,’’ said Sullivan. “I thought I was fine.’’

Now let’s go to Jan. 27 of this year.

Omar’s driving in Atlanta, where he’s been living since summer. The police do one of those random scans of his license plate, and up pops a warrant for his arrest on those charges he thought were gone.

Clink, clink.

Sullivan is put behind bars and, since he’s considered a fugitive, he goes to county jail with the big boys who are all facing serious criminal charges. He tries to tell anyone who might listen that he’s innocent — officers, the jail staff, inmates.

“If you brought me a snack, I told you,’’ he said. “If you threw me a towel, I told you; a bar of soap, I told you. … Anybody I possibly could, I told.’’

Sullivan sits in county for 12 days before being extradited back to Essex County.

In the meantime, he said, he loses his job as manager of a storage company. He loses the apartment he’s about to move into, his car gets impounded and his dog dies at a cousin’s house after it stopped eating with him not around.

All the while, on the other end, his mother, Valerie Murphy of Kearny, takes the letter from 2008 and heads to the courthouse in Newark, thinking the mix-up will be solved.

She should have known better.

Suddenly, through yet another error, an investigator in the prosecutor’s office tells her that her son’s fingerprints match Sylvester’s. Murphy said she then calls Branch, who had signed the letter. She couldn’t reach her but says she got a voice mail message from Branch saying it’s out of her hands.

The sheriff's department, which took his prints in 2008, was unable to clear it up either.

What about the letter from Branch? Apparently useless. By the way, it's real — we've seen it.

Back in Atlanta, Sullivan is handcuffed and put into a paddy wagon on a harum-scarum four-day trip back to Newark that zigzagged its way through several states, dropping off and picking up prisoners in Tennessee, South and North Carolina, Virginia, West Virginia, Kentucky, Ohio, Maryland and Pennsylvania.

The ride is brutal, Sullivan says, and the food just as bad. Two cheeseburgers per man from the $1 menu at McDonald’s and a bottle of water every eight hours. And no fries, either.

Surprisingly, though, and maybe naively, Sullivan says he was glad to get back to Newark.

Maybe then authorities could check out his story fully and free him, he thought.

Wrong for the third time.

When they popped open the back doors of the van, they didn’t call out his name, they called for Steven Sylvester.

“That,” says Sullivan, “is when I knew that this wasn’t going to be fun.’’

Nobody would double-check his information, he says, until his mother hired an attorney, Felix Lopez Montalvo, who asked for a bail hearing on Feb. 19 and explained to Assistant Prosecutor Jessica Guarducci that the system had the wrong fella.

The attorney had a picture of Sylvester, a 190-pound Hispanic man, and of Sullivan, who is black and weighs 145 pounds.

Kathy Carter, spokesperson for the prosecutor’s office, said Guarducci, with the help of the initial investigator, dug up the original file from 2006. It showed that Sylvester was indeed Hispanic and that Sullivan had been telling the truth. Judge Martin Cronin dismissed the case on the afternoon of Feb. 21, and Sullivan figured he’d be out that evening.

Wrong for the fourth time. No one had put his name on the list to be discharged from the county jail.

“I’m not believing this,’’ he said.

He finally got out early Sunday morning, Feb. 23, between midnight and 12:30 a.m.

That’s 16 days in custody, including Atlanta and the extradition travel and another 11 days in Newark. That’s 27 in all.

And how did this happen?

In interviews with The Star-Ledger, the prosecutor’s office and the sheriff’s department said it was a human error. Sullivan’s fingerprints and State Bureau of Identification number got mixed up with Sylvester’s fingerprints and SBI number.

Whenever someone is arrested or fingerprinted, Carter said, they receive the SBI number, which is similar to a Social Security number. It contains your name, date of birth, address and age, and it stays with you in the system. Well, somehow Sullivan mistakenly became Sylvester.

“We know it was some sort of human error, but we don’t know where it occurred,’’ Carter said. “At the conclusion of the investigation, we’ll see to it that his (Sullivan’s) record is corrected.”

Essex County Sheriff Armando Fontoura echoed the same thought.

“It’s a very complicated matter, but unfortunately human error occurs. He appears to be a victim of that. Somebody dropped the ball.’’

When you combine the mix-up with the fact that officers rely on fingerprints to identify you, nobody was going to believe the poor guy or his mother.

“I don’t think he was ever put into the system correctly,’’ said Patrick Metz, his new attorney. “They thought he was Sylvester from day one.’’

Now, are you sitting down?

Sullivan is still not in the clear. His fingerprints, unfortunately, are still linked to Sylvester in the court system.

“I want a clarification on the dismissal indicating in a letter that they were completely at fault for his incarceration and that this should never come up again,’’ Metz said.

The prosecutor’s office and sheriff’s office said they are working on getting Sullivan squared away so he doesn’t ever have this problem again.

After a fresh haircut this week, Sullivan is figuring out his next move. He’s trying to get back his job in Atlanta. He left for down South yesterday. News that his fingerprints are still connected to Sylvester has him worried.

“I can’t take these people,’’ Sullivan said. “I never thought in a million years that I would be in this position.’’

Omar is 33 now. I meant to mention that before this craziness, he had a clean record.

What’s more, because of the mess, ol’ Sylvester is still free as a bird.

Nobody knows where he is. And Sylvester, you may not know this, but what a lucky man you’ve been.

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