The Social Security Act of 1935 authorized the SSA to establish a record- keeping system to help manage the Social Security program and resulted in the creation of the SSN. SSA uses the SSN as a means to track workers’ earnings and eligibility for Social Security benefits. Through a process known as enumeration, each eligible person receives a unique number, which SSA uses for recording workers’ employment history and Social Security benefits. SSNs are routinely issued to U.S. citizens, and they are also available to noncitizens lawfully admitted to the United States with permission to work. Lawfully admitted noncitizens who lack DHS work authorization may qualify for an SSN for nonwork purposes when a federal, state, or local law requires that they have an SSN to obtain a particular welfare benefit or service. In this case, the Social Security card notes that the SSN is “Not Valid for Employment.” As of 2003, SSA had assigned slightly more than 7 million nonwork SSNs. Over the years, SSA has tightened the requirements for assigning nonwork SSNs. In 1986, Congress passed the Immigration Reform and Control Act (IRCA), which made it illegal for individuals and entities to knowingly hire and continue to employ unauthorized workers. The act established a two- pronged approach for helping to limit the employment of unauthorized workers: (1) an employment verification process through which employers are to verify newly hired workers’ employment eligibility and (2) a sanctions program for fining employers who do not comply with the act. Under the employment verification process, workers and employers must complete the Employment Eligibility Verification Form (Form I-9) to certify that the workers are authorized to work in the United States. Those employers who do not follow the verification process can be sanctioned. SSA has two types of data useful to identifying unauthorized work— individual Social Security records and earnings reports. Its individual records, which include name, date of birth, and SSN, among other things, can be used to verify that a worker is providing the SSN that was assigned to a person of that name. These records are used in verification services that are available free of charge to employers on a voluntary basis. SSA’s earnings reports could also be used to identify some unauthorized work by reporting noncitizens who may have worked without authorization and employers who have a history of providing SSN/name combinations that do not match SSA records. SSA uses individual Social Security records in its Employee Verification Service (EVS) and the Web-based SSN Verification Service (SSNVS), which employers can use to assure themselves that the names and SSNs of their workers match SSA’s records. The services, designed to ensure accurate employer wage reporting, are offered free of charge. Employer use is voluntary. Although these systems only confirm whether submitted names and SSNs match, they could help employers identify workers who provide an SSN with fictitious information. Over the years, SSA has developed several different verification methods under EVS. For example, employers may submit lists of workers’ names and SSNs by mail on a variety of media, such as magnetic tapes or diskettes. Alternatively, employers may call a toll-free number or present a hard-copy list via fax, mail, or hand delivery to a local SSA office. SSA verifies the information received from employers by comparing it with information in its own records. SSA then advises the employer whether worker names and SSNs match. EVS offers the benefit of verifying name and SSN combinations for a company’s entire payroll. However, the system would not be able to detect a worker’s misuse of another person’s name and SSN as long as the name and SSN matched. Employers do not widely use this service. In an attempt to make verification more attractive to employers, in 2005, SSA implemented the Web-based SSNVS. It is designed to respond to employer requests within 24 hours. Requests of up to 10 worker names and SSNs can be verified instantaneously. Larger requests of up to 250,000 names can be submitted in a batch file, and SSA will provide results by the next business day. While this new system is attracting more employer interest, it is still not widely used. SSA also uses its records in a work eligibility verification system developed by DHS called the Basic Pilot, which offers electronic verification of work authorization for newly hired workers. Use of this program by employers is also voluntary, and the service has been available nationwide only since December 2004. Employers who agree to participate must electronically verify the status of all newly hired workers within 3 days of hire, using information that a new hire is required to provide. Under this program, an employer electronically sends worker data through DHS to SSA to check the validity of the SSN, name, date of birth, and citizenship provided by the worker. SSA records are used to confirm information on citizens. For noncitizens, SSA confirms SSN, name, and date of birth, then refers the request to DHS to verify work authorization status against DHS’s automated records. If DHS cannot verify work authorization status for the submitted name and SSN electronically, the query is referred to a DHS field office for additional research by immigration status verifiers. If SSA is unable to verify the SSN, name, and date of birth or DHS record searches cannot verify work authorization, a tentative nonconfirmation response is transmitted to the employer. After checking the accuracy of the information and resubmitting the information, if necessary, the employer must advise the worker of the finding and refer him or her to either DHS or SSA to correct the problem. During this time, employers are not to take any adverse actions against those workers related to verification, such as limiting their work assignments or pay. When workers do not contest their tentative nonconfirmations within the allotted time, the Basic Pilot program issues a final nonconfirmation. Employers are required to either immediately terminate employment or notify DHS of their continued employment. Like SSA’s verification services, the Basic Pilot is voluntary and is not widely utilized. As of January 2006, about 5,500 businesses nationwide had registered to participate, although a significantly smaller number of these are active users. Active participants have made about 4.7 million initial verification requests over a 5-year period (981,000 requests were made in fiscal year 2005). DHS reported on actions taken to address weaknesses in the program that had been identified during the early years of the program. They included delays in updating immigration records, erroneous nonconfirmations, and program software that was not user friendly. We subsequently reported on additional challenges, specifically, the capacity constraints of the system, its inability to detect identity fraud, and the fact that the program is limited to verifying work authorization of newly hired workers. SSA’s earnings records can also provide information on unauthorized work. There are two sets of data that are relevant to unauthorized work. The first set, the Nonwork Alien File, contains earnings reports for SSNs that were issued for nonwork purposes. The second set, the Earnings Suspense File, contains earnings reports in which the name and SSN do not match. Both could help identify some unauthorized work. SSA is required by law to provide its Nonwork Alien File to DHS since it suggests a group of people who are in the United States legally but may be working without authorization. Since 1998, SSA has provided DHS annual data on over half a million persons with earnings listed under nonwork SSNs. The file includes annual earnings amounts, worker names and addresses, and employer names and addresses as well. DHS has found this file to be of little use to enforcement activities, however. According to DHS officials, the file is currently not an effective tool for worksite enforcement due in part to inaccuracies in the data and the absence of some information that would help the department efficiently target its enforcement. In fact, because SSA only updates work authorization status at the request of the SSN holder, individuals in the file may now be U.S. citizens or otherwise legal workers who simply have not updated their status with SSA. Our ongoing work in this area suggests that a number of these records are indeed associated with people who later obtained permission to work from DHS. SSA policy is to update work authorization status when the SSN holder informs the agency of the status change and provides supporting documentation. Unless the individual informs SSA directly of the status change, SSA’s enumeration records will continue to show the person as unauthorized to work and will record his or her earnings to the Nonwork Alien File. Currently, the extent to which such noncitizens are included in the file is unknown, but SSA and DHS officials have both acknowledged that the file may include a number of people who are currently authorized to work. DHS officials said that the file would be of greater value if it contained DHS’s identifying numbers—referred to as alien registration numbers. According to DHS officials, because persons in the file do not have an identifier in common use by both agencies, they cannot automatically be matched with DHS records. As a result, DHS officials told us that they use names and birth dates to match the records, which can result in mismatches because names can change and numbers in birth dates may be transposed. SSA officials have said that generally they do not collect alien registration numbers from noncitizens. Collecting the alien registration number and providing it in the Nonwork Alien File is possible, they stated, but would require modifications to SSA’s information systems and procedures. They also noted that SSA would only be able to collect the alien registration number when noncitizens are assigned an SSN or when such an individual updates his or her record. As part of its procedures, SSA is required to verify the immigration status of noncitizens before assigning them an SSN, which requires using alien registration numbers.