MINNEAPOLIS (WCCO) — The person of interest in the Jacob Wetterling investigation cannot be charged with kidnapping and raping another Minnesota boy.

A masked gunman abducted Wetterling in 1989, not far from the 11-year-old’s home in St. Joseph.

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Investigators named 52-year-old Danny Heinrich as a person of interest in the case Thursday.

They charged him with having child pornography and said he denied any involvement in Wetterling’s disappearance.

But prosecutors say DNA evidence does connect Heinrich to another crime, the kidnapping and sexual assault of a boy named Jared.

That attack happened in Cold Spring just nine months before Wetterling vanished.

Jared later came forward in hopes of solving both cases.

In 1989, the FBI believed the person who kidnapped and sexually assaulted Jared was the same person that abducted Wetterling.

Investigators say they now have DNA evidence to link Jared’s assault to Danny Heinrich. But Heinrich will likely never be tried for the alleged crime.

“You have to look at when the crime happened,” Minneapolis attorney Joe Tamburino said.

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He says federal law had a five-year statute of limitations on kidnapping in 1989. It was three years for state law.

“Back in 1989, the kidnapping statutes, basically if you didn’t bring the action between three and five years for state or federal, then you couldn’t make the charge,” Tamburino said.

And it was a similar case for sexual assault. Twenty-six-years ago, the statute of limitations was nine years, or three years after the offense was reported.

“That probably is a firm statute of limitations. There’s not going to be a loophole,” Hamline University law professor David Larson said.

Larson says it is unlikely to change the rules from 1989 for certain cases because of constitutional challenges. But he does believe that the Heinrich case is one that could influence change going forward.

“It’s tremendously frustrating, and that’s why there’s a lot of discussion now about how does DNA evidence change the world. And is there something we can do to kind of revive these cases because we didn’t have any of this evidence available,” Larson said.

Minnesota went to a no-limit on kidnapping in 2000. Federal law followed suit in 2006.

The laws changed, but cannot be applied retroactively to 1989.

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Statute of limitations also does not apply in any type of murder case. So if a body is recovered years later in any case, a suspect can be tried at any time.

John Lauritsen