It was deemed an upset by many in Broome County  when longtime District Attorney Gerald Mollen was unseated by newcomer Steve Cornwell back in 2015.

Four years later, Cornwell is stepping away from the position to run for Congress.

The county faced several challenges during Cornwell's time in office, from the opioid epidemic to a skyrocketing crime rate and security issues at local schools.

"It's been so rewarding but it's the right decision for me in my life at this point and mission accomplished," Cornwell said. "I said what I wanted to do and I did what I said I was going to do."

When Cornwell took office in 2016, a record 76 people died due to drug-related overdoses.

He quickly worked to further developed the county's "drug court" allowing low level offenders to be sentenced to treatment rather than jail.

His "Operation Safe" then brought together a team of individuals to crack down on major drug traffickers.

Overdoses dropped to 32 in 2018.

"We arrested, convicted and sentenced more drug dealers to state prison than in the past decade, so we increased those numbers substantially, so we're taking out drug dealers on one hand and we're getting people into treatment on the other hand," said Cornwell.

The office will now be led by Cornwell's chief assistant, Michael Korchak.

Korchak prosecuted some of those major drug trials.

The current DA said he's confident the county will continue to move in the right direction.

"I'll be watching from a different seat and a different view but I'm very excited for what's in store for Broome County in the future and it's really time this area gets back to what it was, the valley of opportunity," said Cornwell.

Cornwell hopes to challenge Rep. Anthony Brindisi in the 2020 election, though he'll face a tough Republican primary with three opponents, including former Rep. Claudia Tenney.