Mr Hashida joined the District of Columbia's Metropolitan Police Department (MPD) in May 2003.
Another MPD officer who responded to the Capitol on 6 January, Kyle DeFreytag, was found dead on 10 July, Mr Carew said. Mr DeFreytag’s cause of death was also suicide, Mr Carew said.
He had been with the police department since November 2016.
MPD Officer Jeffrey Smith and US Capitol Police Officer Howard Liebengood also responded to the Capitol riot and later died by suicide.
Hundreds of then-President Donald Trump supporters stormed the building that day in an unsuccessful attempt to stop Congress from certifying Democratic President Joe Biden's election win.
Four people died on the day of the violence.
A Capitol Police officer who had been attacked by protesters died the following day. More than 100 police officers were injured.
The mayhem led to Mr Trump's second impeachment trial. More than 500 people have been arrested for their roles in the violence.
During emotional testimony last week, four police officers told a House of Representatives special committee probe into the incident that they were beaten, threatened, taunted with racial insults, and thought they might die as they struggled to defend the Capitol against the mob.
It was "something from a medieval battle," Capitol Police Sergeant Aquilino Gonell, an immigrant US Army Iraq combat veteran, told the panel, describing how he and colleagues "fought hand to hand, inch by inch, to prevent an invasion" of the building.
"My fellow officers and I were punched, kicked, shoved, sprayed with chemical irritants and even blinded by eye-damaging lasers by a violent mob who apparently saw us... as an impediment to their attempted insurrection," St Gonell told stunned committee members.
"This is how I'm going to die, defending this entrance," he recalled telling himself.
Mr Trump has dismissed the probe as "fake and highly partisan" and attempted to blame Democrats for allegedly failing to protect the Capitol, accusations echoed by his Republican backers.
Readers seeking crisis support can contact Lifeline on 13 11 14, the Suicide Call Back Service on 1300 659 467 and Kids Helpline on 1800 55 1800 (for young people aged up to 25). More information and support with mental health is available at Beyond Blue.org.au and on 1300 22 4636.
Embrace Multicultural Mental Health supports people from culturally and linguistically diverse backgrounds.