A Nova Scotia woman is asking for the public’s help in solving her sister’s murder after charges laid in the case were dropped this week.

Jenn Corbin believed justice would be served, but now she says her hope has vanished.

“What they are doing is not taking away our rights. They are taking away Rhonda’s rights and that’s not fair to Rhonda,” says Corbin. “She didn’t deserve to have what happened to her.”

Rhonda Wilson, a 31-year-old mother of three, was last seen on Aug. 7, 2002 when she left her Kentville, N.S. home to go for a walk.

Her common-law partner, Albert Baird, reported her missing to police three days later, on August 10.

Baird was arrested in May 2013 and charged with first-degree murder in Wilson’s death.

“We waited so long to get a charge and we honestly didn’t think we’d ever get to that point,” says Corbin.

However, the Crown has withdrawn the charge against Baird after concluding there was no realistic prospect of conviction. In making its decision, the Crown considered a recent Supreme Court of Canada decision on Mr. Big operations.

During such operations, undercover police officers recruit a suspect to a fake criminal organization in order to obtain a confession about a prior crime or crimes.

The high court noted several problems with the Mr. Big strategy in its July 31 ruling, overturning the conviction of Nelson Hart in the deaths of his young daughters in Newfoundland in 2002.

Before his arrest, Baird was allegedly caught in a Mr. Big sting, and while the Supreme Court has not called for an end to Mr. Big sting operations, it ruled that police must implement more stringent guidelines for their use.

Under the ruling, confessions obtained through a Mr. Big sting are inadmissible in court if they are not accompanied by corroborating evidence.

Wilson’s remains have never been found and the Crown says it isn’t confident the evidence recovered during the undercover sting is enough to convict Baird in court.

As a result, the charge has been withdrawn and Baird has been released from custody.

“Honestly, I think they are holding the criminal’s hands,” says Corbin. “I think they are letting them get away with these things.”

The investigation into Wilson’s death is still active but police say they need more evidence.

Corbin says she fears her family will never know exactly what happened to her sister, or see justice for her murder.

“We are just looking for anyone with any information to go contact the police.”

With files from CTV Atlantic's Kelland Sundahl