USCIS has recently stated that background checks for immigrants who wish to become permanent residents have been loosened. This is an attempt to reduce the large backlog of green card applications for the thousands of immigrants currently living in the United States who have no criminal record, but have been waiting for years because the FBI name check showed a match against their names.
According to the USCIS memo, immigration officers will be permitted to approve a petition for a permanent residence if the petitioner has been waiting more than six months and the only missing piece is the FBI name check. A green card can be cancelled and the immigrant deported if his or her application for permanent residence is approved, but after approval, an FBI name check shows negative information about the immigrant.
Under the new policy however, applicants for permanent residence must still complete two other security checks, an FBI criminal fingerprint check and a search of federal criminal and anti-terrorist database. Furthermore, a permanent resident may not become a citizen until his or her name check has been completed.
For more details see Aytes Memo dated February 04, 2008.