Evidence

What is the name of your state? Texas

Some one I know has been in prison for 19 years for rape, 1st and only offence. He's sentence to 99 years. We're trying to get a DNA test done but if they can not find the evidence to have the test could the case be thrown out? And could he be set free?

Most laws limit the retention of evidence in cases that have brought a conviction to 10 years. The current lack of evidence is not enough to warrant having the sentence suspended. Besides, 19 years is well beyond the statute of limitations for appeal unless new compelling evidence is presented.