Juan Santana, a brother-in-law of alleged Etan Patz killer Pedro Hernandez and the manager of the Soho bodega where prosecutors say the crime occurred in 1979, told the judge Friday that he has decided to take the Fifth Amendment and decline to testify at the retrial of the case.

Santana testified at the first Patz trial last year that Hernandez was living at his apartment with his wife and three children in 1979, and that he was working as a stock boy at the bodega on the day 6-year-old Etan disappeared on his way to catch a school bus at a nearby stop.

But he couldn’t remember details, including how soon Hernandez left New York after the boy disappeared, and prosecutors portrayed him as evasive.

In opening statements for the new trial last week, prosecutors told jurors Santana was hiding something and that triggered his claim that new testimony could make him a target for a perjury case.

Justice Maxwell Wiley said prosecutors next week will be permitted to read to jurors Santana’s testimony from last year, and they have also called his wife, Hernandez’s sister, to the stand as a new witness.

The defense says prosecutors are trying make their bad memories appear suspicious.

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Hernandez, 55, of Maple Shade, New Jersey, is accused of killing Etan in the bodega basement.

He confessed after a relative tipped police in 2012 that he made incriminating remarks, but the defense says he has delusions due to a mental disorder. The first trial ended in a hung jury.