Under current legislation police and immigration can only look into the telephones of refugees if they are suspected of committing a crime or if they consent to the search.
The mobiles, authorities say, could swiftly clear up the backlog by pinpointing the real nationalities of the suspect migrants.
Without a true identity, they cannot be deported.
Now the interior ministry is presenting a bill to the national parliament which is expected to be passed unopposed giving the Bamf – the Federal Office for Migration and Refugees – software to read the data cards of thousands of mobile phone users daily.
The software will also be deployed to try to trace refugees who have vanished off the radar and may be “sleepers” of the Islamic State.
Yesterday it was revealed that in the state of Brandenburg alone more than 3,000 migrants have disappeared and are unaccounted for.
Amri, a Tunisian who was shot dead five days after the December 19 attack after fleeing to Italy, had used 14 aliases to fool authorities in the country.
Tapping into mobile phone data will lead to friends, acquaintances, relatives in the true homeland of refugees.
Authorities also believe it will be instrumental in cracking down on massive monetary fraud committed by some migrants using multiple identities in many different towns to draw benefits.