MIAMI (CBS4) – During the holidays, many people open their hearts and wallets and make donations to charity.

But do they know where their donations are going. CBS4 Chief Consumer Investigator Al Sunshine found some ‘causes’ may be only receiving pennies on the dollar.

“There are a lot of great charities out there, but there are also some scoundrels and thieves,” said Ken Berger, CEO and president of Charity Navigator, a national watchdog group tracking non-profit organizations.

So.why do they need a watchdog?

“You know, it’s estimated to be as much as two trillion dollars of the American economy. That’s one out of every ten jobs,” said Berger.

At CharityNavigator.org, people can find out how a charity spends its donations and how much actually goes to the mission it supports.

Imagine, for example, you want to donate a $100 to a specific charity.

According to Charity Navigator, The U.S. Marine Corps’ Toys for Tots Foundation would put$ 97 of those dollars toward its programs. The American Red Cross would put $92 to its causes.

But according to Berger and his group, the American Cancer Society would use just $70 for its main mission and the March of Dimes would apply only $64 to its cause.

There are also some surprises.

The National Police Defense Foundation would pass along only $17 dollars to officers.

The National Vietnam Veterans Foundation, meanwhile, would give only nine dollars to veteran’s causes.

“It was a big surprise to us how much poor performance we found among organizations that help police, firefighters, and veterans,” said Berger.

The National Police Defense Foundation’s founder said the organization doesn’t have the personnel to solicit donations, so it hires ‘professional fundraisers’ who are paid up 75% of a donation.

Berger said a charity’s biggest mistake is depending on telemarketers, who sometimes keep the entire donation.

“Our advice is to hang up the phone and never give over the phone,” said Berger.

American Red Cross spokesperson Anita Foster is proud to see her organization ranked highly in efficiency but she said there will always be bills to pay.

“There’s overhead. There’s a cost of doing business. We have to have the lights on in the building. We have to put gas in our vehicles,” said Foster.

The US government requires most non-profits to disclose their finances which means anyone can check on how and where their money is being spent.

“It’s perfectly okay to make a decision based on where your heart lies, but also make sure it is a responsible non-profit that will use your money wisely,” said Foster.

Charities operating in Florida have to be registered with the state’s Department of Consumer Services. They also have to list how much goes towards administration and charity services.