As an officer committed to tackling illicit drugs in Wollongong at the height of the heroin epidemic in the early 1990s, Detective Inspector Dennis Clarke knows what it's like to see the worst side of humanity.
For Insp Clarke, the hardest part of his 40 years with the NSW Police Force was witnessing the victims of horrific crimes, and relating them back to his own family.
"As a police officer, people often forget you do have family and so the things you see in life do have a greater effect on you," he said.
But one of his greatest career highlights was the knowledge he had made a difference to the community when bringing those who were "peddling misery" to justice.
"You felt some achievement when you were able to arrest, charge and convict drug suppliers," he said.
On Friday, Insp Clarke joined four other retiring officers with almost 200 years of combined service at the NSW Police Academy for an official farewell from duty.
Insp Clarke has witnessed a lot during his 40 years in the force but he said he would miss the comradeship among his fellow officers the most.
"There's mixed emotions as to where I am," he said.
"There are a lot of good people you meet and work with along the way but I think I know when you reach your best-before date.
"After 40 years, it's about time to hang up the hat."
Insp Clarke was sworn in as a probationary constable on September 19, 1973, and attached to Sutherland police station on general duties before moving on to Wollongong criminal investigations.
He spent the last nine years of his career as the Professional Standards Manager, Southern Region, and will complete his last day of service on September 19.