GRAFENHAUSEN, GERMANY — Some members of the prosecution in the Mike Peterson trial who traveled to Germany said they have had a productive trip so far.

Prosecutors Freda Black and David Sackes, along with Detective Art Holland, traveled to Germany to further investigate the death of Peterson's friend, Elizabeth Ratliff. Authorities say Ratliff died under similar circumstances to Peterson's wife, Kathleen. Both women were found at the bottom of a staircase.

On Thursday, prosecutors went to Ratliff's former house to examine the staircase where she died. The prosecution team met with German investigators Friday in hopes of receiving police records associated with Ratliff's death. Peterson had said that Ratliff had died of natural causes, but prosecutors believe Ratliff was murdered by Peterson. However, getting those police records has been troublesome.

German authorities said the Minister of Justice has to approve the prosecution's request and German prosecutors say they have concerns.

If a murder investigation is opened and Peterson is charged with Ratliff's death, he would not be charged in the United States and would not face the death penalty.

German authorities say they will decide by June 30 if they will launch a murder investigation into Ratliff's death.