Debt collectors are hounding Americans who owe, and consumers are speaking up. According to the Federal Trade Commission, the number of consumer debt-collection complaints filed in 2010 was up 17% from 2009, to 140,036.

More debt collection complaints were received in 2010 than complaints from any other industry, the FTC said in its annual report. Of those complaints, 54,147 consumers said they were repeatedly called and harassed by collectors and 27,554 consumers said collectors had threatened them with illegal claims -- like seizure of property or prosecution. A smaller group, 4,182 consumers, said that collectors threatened violence.

FTC Spokesperson Frank Dorman said the agency is unsure of why complaints are up for debt collection, but it is likely due to the economy.  So many people are unemployed or under-employed that it would make sense for both legal and illegal debt collection practices to increase.

"Debt collection has increased, and along with legitimate debt collection that uses acceptable practices, you will find there are more aggressive practices that are against the law," Dorman said.

Consumers are becoming more aware of their own rights involving debt collection, even if they do owe money, they are learning what collectors can and cannot do, he said.

"More people are aware that there are laws to protect them," Dorman said. "They can file a complaint with the FTC, or their state's attorney general's office, and some consumers will also have right of private action and can file a suit."

Personal Finance Expert Gerri Detweiler of Credit.com said that the spike in complaints could also be due to the popularity of debt buying.

"There are a lot of buyers that are purchasing old debts, and some are especially aggressive in trying to collect from consumers," Detweiler said. "That leads to complaints."

Overseas credit scams may also be contributing to the increase in consumer complaints, she said. These companies, mainly based out of India and Pakistan, harass consumers incessantly, Detweiler said.

"They don't care if they are breaking the law, because they are not here to be caught," she said.

Most likely, Detweiler said, the FTC is correct in its thinking that the economic climate is leading to more consumer complaints.

"People have a tough time paying bills, and debt collectors have a tough time collecting their money," she said. "You can have either aggressive debt collectors or frightened consumers, and when those merge it can lead to increased numbers."

Although the FTC does not act on behalf of individual consumers, Dorman said that if the agency receives multiple complaints about a particular practice or company, it will take action.

"We might end up suing the company," Dorman said. "These are very time-consuming cases that affect lots of consumers. We have to determine who we will and won't go after."

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