* Decline attributed to pending litigation
* Budget issues, redistricting bigger priorities this year
By Tim Gaynor
PHOENIX, Aug 6 (Reuters) - U.S. state legislatures passed fewer immigration measures this year because lawmakers' priorities shifted to balancing budgets and U.S. courts were weighing how much authority states have to enforce immigration laws, according to a study released on Monday.
The National Conference of State Legislatures found 41 states enacted 114 bills and adopted 92 resolutions relating to immigrants and refugees in the first six months of this year, a decline of 20 percent compared to the same period in 2011.
"Legislators found that state budget gaps and redistricting maps took priority, consuming much of the legislative schedule," according to a report by the group's Immigration Policy Project.
"Perhaps more significant, state lawmakers cited pending litigation on states' authority to enforce immigration laws as further reason to postpone action," it added.
Immigration, particularly what to do about 11 million undocumented immigrants living and working in the shadows nationwide, has been a divisive issue in this nation of immigrants.
Arizona Republican Governor Jan Brewer signed a law two years ago designed to drive undocumented immigrants out of the border state. Parts of the law were later blocked by a federal judge.
Last year, Alabama, Georgia, Indiana, South Carolina and Utah also cracked down on unauthorized immigration. But the laws passed in those states were either partially or entirely blocked by the courts.
In June, the U.S. Supreme Court upheld the most controversial provision of Arizona's law, which requires police to check the immigration status of people they stop, but it threw out three other provisions.
Still pending in Arizona is a lawsuit that tests additional constitutional questions not addressed in the recent Supreme Court ruling.
In 2011, 30 state legislatures introduced more than 50 broad immigration bills similar to Arizona's. Five states, including Kansas, Mississippi, Missouri, Rhode Island and West Virginia, have done so this year, but none were enacted, according to the report.
Alabama amended its law this year to require police to detain people they suspect of being in the United States without documentation if they cannot produce proper documentation. The law also targets those harboring and transporting undocumented immigrants.
Legislation related to identification and driver's licenses remained top issues addressed by state legislatures, accounting for 18 percent and 11 percent, respectively, of all immigration laws enacted in the first half of 2012, the report said.
States continued to approve legislation that funds naturalization, migrant and refugee programs, according to the report. Laws related to those programs made up about one-quarter of the laws passed in the first half of 2012, the study said. (Editing by Stacey Joyce)