Gov. Haley Barbour has signed into a law a bill that requires the state to preserve biological or DNA evidence gathered in felony investigations.

Many law enforcement agencies across the state gather DNA during investigations, but the samples aren’t always preserved. The bill, which goes into effect immediately, requires the evidence to be maintained by either by the Mississippi State Crime Lab or local law enforcement.

The new law was inspired, in part, by the 2008 exoneration of Kennedy Brewer, who had been convicted of capital murder in the rape and strangulation of a 3-year-old girl. DNA cleared Brewer in the attack years after he had been sent to death row.

Among other bills signed by Barbour on Monday were those that would:

— Grant visitation rights to grandparents who cared for a child for an extended period of time while the child’s parent was in jail or serving military duty.

— Make it a misdemeanor for a person under age 21 to show false identification to buy alcohol.

— Require county boards of supervisors to establish an indigent burial policy and authorize the full payment to bury those who are deemed paupers when they die.

The bills are Senate Bills 2709, 2136, 2616 and 2504.