A few years ago, Deputy Inspector Brad Wentlandt and Captain Paul Schlecht were trying to come up with a way to honor citizens who went the extra mile to help the Greenfield Police Department.

Their idea: Challenge coins.

Challenge coins are believed to have originated in the Army Air Corp (now known as the United States Air Force) in World War I. They were intended to foster camaraderie among a group.

"The thought is that if you are carrying your coin at all times, it is a constant reminder of the group's mission, goals and ethics," Wentlandt said. "For us, the coins represent our commitment to service and the department mission."

For the Greenfield Police Department, the coins are also a symbol of the special bond between it and the citizens of Greenfield.

"The whole point of issuing them to citizens is to provide a way to immediately recognize citizen involvement in a meaningful way," Wentlandt said. "It's a way to welcome the citizen  into our group and strengthen the partnership."

Each officer in the department carries the coin at all times and has complete discretion when to issue it to a citizen. When the officer does so, he or she sends a memo detailing the event to the administrative staff and a replacement coin is issued to the officer.

In early December, the department invites all coin recipients to its Citizen Recognition and Awards Ceremony, where a synopsis of the event is read and a cherry wood presentation case is given to each recipient.

Schlecht designed the coins with a city logo on one side and a police badge on the other, and the police department began giving them out in 2009. That year, they issued eight. Last year, the number increased to 21, and this year, the first two coins were issued to a pair of Department of Public Works employees who helped thwart an alleged drug deal while they were out cutting down a hazardous tree.

Coin-deserving acts do not necessarily have to be those of heroism or bravery. According to Wentlandt, the department has issued coins for something as simple as finding and returning a lost department cell phone.

In the same breath, however, he said the department does not hand out the coins like candy in a parade.

"It's important to note that these coins are rare," Wentlandt said. "We don't give them out except to our officers and then to citizens who go above and beyond. We don't give coins to friends or relatives. These things aren't trinkets. They have real meaning. If we were to allow them to be given out for any other reason it would cheapen the meaning."