The long history of why Officer Sean Gannon's murder suspect wasn't in jail

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YARMOUTH, Mass. — The man charged with shooting and killing Yarmouth K-9 Officer Sean Gannon could’ve been sent back to jail several times, according to a 25 Investigates review of state records.

A warrant was issued for Thomas Latanowich’s arrest for a probation violation last week, but it was hardly the first time Latanowich violated probation.

Court records also show he has a well-documented history of being armed and dangerous.

Prosecutors say Latanowich shot and killed Officer Sean Gannon as he and his K-9, accompanied by a team of officers, attempted arrest him on a warrant. 25 Investigates has learned the warrant was issued after Latanowich missed a visit from a probation officer and failed to show up for a drug test last week.

Police say they found Latanowich barricaded in the attic of a Marston Mills home after he fatally shot Gannon.

Officer Gannon, 32, who died from his injuries Thursday night, was hailed as a “rising star” by his police chief.

On Friday morning Latanowich was held without bail and charged with Gannon’s murder.

But it wasn’t Latanowich’s first appearance in court.

Thomas Latanowich’s criminal history appears to stretch back to July 2005 – when he first appeared in a Yarmouth courtroom.

He was charged with negligent driving, driving without a license and a crash causing personal injury and fleeing the scene. Those charges were later dismissed, but was just the beginning of Latanowich’s 13-year involvement with Barnstable County's justice system – which included 114 prior charges.

So why was he on the streets in the first place?

“The public most certainly should be asking these questions,” said Boston 25 News Legal Analyst Peter Elikann. “These are darn good questions to ask. We would have to do an awful lot of investigation to see if somebody dropped the ball.”

MORE: Tributes pour in for fallen Yarmouth Police Officer Sean Gannon

Court documents obtained by 25 Investigates from Barnstable and Middlesex counties tell the tale of Thomas Latanowich and his nearly innumerable court appearances.

Court records show he was convicted in 2010 and spent almost four years in prison for assault, witness intimidation, drug possession and gun charges.

Indictments reveal Latanowich had an arsenal of high-powered rifles, shotguns and thousands of rounds of ammunition.

But Latanowich also dodged a number of charges. The courts dismissed several charges for unlicensed weapons possession and possession or trafficking in drugs as well as at least one count of motor vehicle theft between 2005 and 2010.

Latanowich was released from prison at MCI Cedar Junction in June 2014 and

Latanowich was released on parole November 1, 2013, but he was back behind bars less than a month later for violating conditions of his parole and later released again on June 24, 2014. Latanowich was ordered to remain on probation until November 1, 2018.

MORE: Suspect accused of killing Yarmouth officer had history of criminal offenses

Parole records show he earned his GED while in prison and completed other programs, including drug recovery, violence prevention and computer skills, while behind bars.

But in October 2016, Latanowich was arrested again and accused of strangling a pregnant woman. He was charged with assault and battery on a pregnant victim, strangulation on a pregnant victim and vandalizing property. He was released on bail.

Prosecutors also filed charges alleging the new arrest violated his probation, a move which could have sent Latanowich back to prison.

But in February, prosecutors were dealt a serious blow when a witness in the case refused to testify. Without that testimony, the case was dropped – along with the probation violation.

But in the meantime, Latanowich’s run-ins with the law continued. He was accused of assaulting someone in December 2016 and locked up at the Barnstable County Correctional Facility.

In April, Latanowich was released from Barnstable County Correctional Facility and remained on probation.

Latanowich was ordered to complete a mental health evaluation and anger management counseling as a part of his probation after his release. But the probation department would not say whether parole officers made sure he complied with those court orders.

MORE: You can contribute to a GoFundMe page for Officer Gannon's family here.