There are thousands of attempts to illegally buy a handgun in the US every year, but only a handful of those people are ever charged with a crime.

To buy a gun from a licensed dealer, a person needs to fill out a form to request a background check. It's called a 4473 form.

A person needs to check off on many things on this form, including stating the person attempting to purchase a weapon is legally allowed to have a gun.

However, a Department of Justice study found from 2008 to 2014 more than 556,000 people filled out a form for a background check and were denied, meaning some information on that form was incorrect.

That's a federal crime; providing false information to a gun dealer. Yet only 254 of those denials resulted in criminal charges, and that frustrates many gun dealers.

The reason prosecutors say so few of these crimes are prosecuted is you have to prove the person knew they were lying, which can be very difficult.

That's one reason Iowa joined other states last year in making it illegal to buy a gun for someone else or to lie to try to buy a gun, making it a state crime. Up until then, it had only been a federal offense.

Despite the numbers, gun dealers like Ken Freiburger, owner of Gun Depot in Dubuque, work hard to ensure all of their transactions are legal.

"They've got to be honest and for God's sake they better be because it's a federal felony," Freiburger said in regards to people filling out the 4473 form.

On top of asking every customer to fill out the 4473 honestly, Freiburger says he always asks if the person if buying the gun for him or herself. In other words, he wants to prevent straw transactions.

"If you're going to do a straw man transaction, no. You bring that customer in and leave him go through the paperwork just like you are so it's a legitimate transaction," Freiburger said.

Buying a gun and then giving it or selling it to someone who is not allowed to have one is a felony, punishable by up to 10 years in prison.

Freiburger said he hates to see or hear about these transactions happening.

He said, "it's aggravating, frustrating and this is why I talk to them, if you're going to buy this weapon it's for you."

Nick Schlosser, Criminal Investigator for the Dubuque Police Department, agrees with Freiburger.

He said, "we don't want the guns to end up in people's hands that shouldn't have the guns and ultimately the people that are lying on these forms are putting those guns in the hands of people that don't and should not have those guns."

Schlosser investigates gun cases for the police department.

He says he sees people lie about their drug use the most on the 4473 form, and that he will charge someone for lying about that.

"The US Attorney's office do prosecute a lot of our cases out of Dubuque County that have been prohibited persons in possession of firearm and a lot of those are drug user in possession of firearms," Schlosser said.

Dubuque County Sheriff Joe Kennedy says his office keeps tabs on the number of guns people buy.

"Anytime you buy more than one we have to be notified and we keep that on file," Kennedy explained.

He says he's rarely notified of someone lying on the 4473 form.

"It's not really something I see as a major problem. If it becomes a major problem then we'll deal with it as we need to," he said.

It's clear law enforcement and gun retailers work together to keep guns in the right hands. Schlosser and Kennedy say the gun retailers in Dubuque do a great job of reporting suspicions, and Freiburger said law enforcement is good about charging people who lie on the 4473 form or sell a gun illegally.