There is no statute of limitations on murder in Arkansas or any other state. That is why the authorities may continue to investigate an unsolved murder for decades. The odds for a conviction, however, are reduced as time passes with no arrest or prosecution. This is due to loss of evidence, loss of witnesses and other reasons related to the passage of time.
One example is a case involving the murder of a Fayetteville woman in 2006. Authorities were not able to solve the case, and no arrest was made for several years. However, in April 2012 the case was reopened and a Springdale man was charged with the crime. Nonetheless, things moved slowly, and the proceedings were held up for the suspect to be evaluated for his mental ability to stand trial.
Medical examiners declared him fit to stand trial as of Dec. 2013. However, prosecutors recently announced that the evidence was insufficient to go forward due primarily to the death of a witness. Based on the rather sketchy news reports, it does not appear that the evidence was ever particularly strong, and it is curious why a witness was available in 2012 and not in 2006. As a murder suspect, the defendant was quickly appointed defense counsel, and it would appear that his counsel has been influential in convincing the authorities to drop the charges.
The prosecution has not apparently revealed what particular evidence emerged in 2012 to justify re-opening the case and making the arrest. It also did not explain this week why there is now insufficient evidence, other than to remark that a "key" witness died. It is important that the defendant's criminal defense counsel remain engaged in monitoring every development in a murder case. Counsel will then be able to aggressively argue to the prosecution that the case should be dropped where there is a lack of evidence under the criminal laws of Arkansas.
Source: 4029tv.com, "Charges dropped against suspect in Nina Ingram murder case", Allison Wise, July 1, 2015