The main problem that German prosecutor Hans Christian Wolters has in linking Christian Brueckner to Madeleine McCann's crime is locating him at the time and place of the crime.
The record of the half-hour call, supposedly received by the suspect, is not enough to locate him at the crime scene. At most, it only locates him somewhere in Praia da Luz between 7:32 p.m. and 8:02 p.m. on May 3, 2007, but not the exact place where he was. In addition, it would be necessary to prove that the suspect was the one who received the call.
Brueckner's psychological and criminological profiles fit very well the type of person who committed Madeleine's crime: an apartment burglar with a history of commiting sexual assaults. It may be suggestive, but a profile proves nothing.
The only witness to a phase of the crime was Jane Tanner, but her account was quite poor, since she did not give importance to the facts at the time, and that reduced her attention. This won't be enough to tie Brueckner to the Madeleine case.
Now we know that the Portuguese investigators did not collect all the possible sources of nuclear DNA at the scene of the crime, hours after it happened. The traces were there, and it is not understood why they were not collected. We are referring to an unknown number of cigarette butts that were found outside, but very close to, apartment 5A.