Is using a forged Social Security Number -- but your own name -- to obtain employment or buy a car an identity theft crime? Lately, U.S. courts are saying it's not.

The most recent judicial body to take on the issue, the Colorado Supreme Court, ruled last month that a man who used his real name but someone else's Social Security number to obtain a car loan was not guilty of "criminal impersonation," overturning convictions by lower courts.

That follows a ruling last year by the U.S. Supreme Court that a Mexican man who gave a false SSN to get a job at an Illinois steel plant could not be convicted under federal identity theft laws because he did not knowingly use another person's identifying number. The ruling overturned an opinion by a federal appeals court in St. Louis -- and contradicted earlier findings by circuit courts in the Southeast, upper Midwest and the Gulf states.

It hasn’t been a shutout for identity theft prosecutors, however. In July, an Iowa state appeals court came to the opposite conclusion, affirming a lower court decision that a man who used a California woman's SSN to obtain employment was guilty of breaking that state's identity theft law.

Identity theft can take many forms, but one of the most vexing is so-called "SSN-only" ID theft. In it, an imposter uses a victim's SSN --- sometimes purchased from a broker, sometimes nine digits pulled out of thin air -- to obtain credit or to provide necessary documentation to obtain work. In many cases, SSN "borrowing" is successful and the imposter goes undetected for years.

At the heart of all these cases is a simple question: Does the mere use of an anonymous victim's SSN break identity theft laws?

Mari Frank, a California-based lawyer and identity theft victim advocate, said courts are failing to recognize the real harm caused by imposters, even if imposters are unaware of that harm.

"You can't say there's no victim,” she said. “That Colorado ruling really aggravated me," she said. Courts are mis-applying impersonation laws, and that could really hurt victims. "(The judges) just don't get it."

Immigrant advocates vs. ID theft victim advocates

Many of the recent cases stem from a series of raids conducted by the Immigration and Customs Enforcement service at meat-packing plants in the Midwest during the waning days of the Bush administration. Prosecutors got in the habit of using federal identity theft laws to seek a mandatory two-year felony sentence enhancement for convicted suspects, and used that threat as bargaining tool to push suspects into plea bargains. But the 2009 Supreme Court ruling essentially took that bargaining tool away from prosecutors.

The issue pits immigration rights advocates -- who say that undocumented workers are fundamentally different from identity criminals trying to steal credit -- against identity theft victim advocates, who think tougher imposter laws are needed.

“An immigrant who uses a false Social Security number to get a job doesn’t intend to harm anyone, and it makes no sense to spend our tax dollars to imprison them for two years," Chuck Roth, litigation director at the National Immigrant Justice Center in Chicago, told the New York Times after the U.S. Supreme Court's ruling.

Get breaking news and insider analysis on the rapidly changing world of media and technology right to your inbox. This site is protected by recaptcha

But the Identity Theft Resource Center argues that immigrants who use SSNs to get employment often end up putting the numbers to other uses: obtaining credit cards or car loans that can ultimately be blended in with the victim’s credit, sometimes with disastrous results. The center took particular exception to the Colorado ruling.

"This is a dangerous precedent that has now been established and which could permit abuses of the system designed to protect innocent bystanders from fraud," the center said in a statement. "The Colorado State Supreme Court has implied it is permissible to use an SSN that was not issued to an individual to establish new lines of credit."

The courts' logic

The U.S. Supreme Court decision was unanimous. In it, the justices found that an immigrant using an unknown person's SSN to obtain work authorization did not "knowingly" use information that belonged to another person, as required by the statute.

The suspect in the case, Ignacio Flores-Figueroa, presented a Social Security card with his name but a false SSN -- the number turned out to belong to a minor -- so he could work at steel plant in East Moline, Ill. He was convicted of immigration offenses and aggravated identity theft and given a 75-month jail sentence, including a two-year enhancement for the federal ID theft charge. His success in the Supreme Court reduced his sentence by 24 months. He is still subject to deportation when he finishes serving his time.

Because Flores-Figueroa did not know if the number was real or manufactured, he did not know the number belonged to another person, so could not knowingly have committed identity theft, the court found.(PDF)

“(The suspect) claimed that the government could not prove that he knew that the numbers on the counterfeit documents were numbers assigned to other people,” the court wrote. “The question is whether the statute requires the government to show that the defendant knew that the ‘means of identification’ he or she unlawfully transferred, possessed, or used, in fact, belonged to ‘another person.’ We conclude that it does.”

Frank, the advocate for victims of ID theft, finds that logic flawed.

"They're saying ... he didn't have the intent to steal someone's identity because he didn't know if it was or wasn't someone's number," she said. "But even if you make up a 9-digit number you should have reason to know might be someone else's number."

Bought car with fake SSN

In the more recent Colorado case, Felix Montes-Rodriguez applied for a car loan at a dealership using his real name, date of birth and employer, but someone else's Social Security number. He had also used the number to obtain employment. Apparently, Montes-Rodriguez had every intention of paying the loan himself – in other words, he was not intending to steal the car -- but needed the number in order to obtain credit. Lower courts found him guilty of the state's criminal impersonation law, but in a split decision, the state's Supreme Court used similar logic to the U.S. Supreme Court in overturning his conviction.

"In the face of so much accurate identifying information, we cannot conclude that Montes-Rodriguez pretended to be another person in his loan application simply because he supplied a false Social Security number,” the justices wrote. “Hence, we conclude that Montes-Rodriguez did not assume a false identity.”

In a fine parsing of language (PDF), the justices also said that SSNs are not a legal requirement for obtaining a loan -- even though they are required by banks -- and therefore using one in a loan application doesn't represent an illegal act.

The dissenting judges were colorful in their objection.

"I not only believe the majority misconstrues the criminal impersonation statute and reaches the wrong result in this case; but by slicing, dicing, parsing, distinguishing and generally over-analyzing (over the course of some 30 paragraphs) one short and relatively self-explanatory phrase, the majority manages to exclude from the statutory proscription conduct lying at its very heart," wrote Justice Nathan Coats, on behalf of the minority.

It is unclear how common SSN-only ID theft is, but the issue is one of many byproducts of the millions of undocumented workers at U.S. companies. Employers are required to obtain right-to-work documents from new hires, including evidence of a valid Social Security number. But illegal aliens commonly buy or copy the numbers, which are rarely checked for accuracy. That means they can work using fake or forged SSNs undetected for years. In a typical year, some 7 million to 10 million workers pay taxes using names and numbers that don't match IRS and Social Security Agency data. Many of these are believed to be illegal immigrants, based on sample studies conducted by the Social Security Administration, but there is no additional published information.

(For more, read this prior story)

Frank says ID theft victims whose numbers are used by illegal immigrants have no way of discovering the compromise -- the information doesn't show up on credit reports or annual Social Security statements. But if immigrants miss a payment or fail to pay taxes, the rightful owner of the SSN often encounters trouble.

That's why she thinks court rulings that diminish punishments against those who use someone else's SSN could endanger victims.

"The SSN is still the keys to the kingdom,” she said. “(The judges) don’t understand that using the SSN itself is tantamount to ID theft. For far too long, the courts and industry have not taken identity theft seriously and here is but another example."