* Minister backs researcher over Church sex abuse study
* Questions Church's commitment to independent investigation of abuse
By Alexandra Hudson
BERLIN, Jan 10 (Reuters) - Germany's Justice Minister praised on Thursday a criminologist sacked by the German Roman Catholic Church over his research into clerical sexual abuse.
Sabine Leutheusser-Schnarrenberger said Christian Pfeiffer was one of Germany's foremost experts in his field and that bishops appeared to have wanted to control which of his findings would eventually be published.
Victims' groups and sympathisers were outraged by the Catholic bishops' decision on Wednesday to sack Pfeiffer, who they commissioned two years ago to bring abuses to light after some 600 people filed claims against priests.
"I can only say that the criminology research institute in Hanover under Professor Pfeiffer is one of the top places for serious investigations," Leutheusser-Schnarrenberger told Deutschlandfunk radio.
"It appears that conducting an independent, serious study into the abuse cases, as originally intended, is impossible for the Church," she said. "This is a shame, as it gives the impression that ultimately they did not want everything to be independently studied."
Investigations into the records of priests accused of molesting children has been conducted in recent years in other countries, sometimes with devastating results for the reputation of the church involved.
The secretary of the German Catholic Bishops' conference, Hans Langendoerfer, said they had lost confidence in the researcher, Christian Pfeiffer, and considered any serious co-operation impossible.
One area of dispute had been data protection for sensitive audio recordings of questionings.
Leutheusser-Schnarrenberger said data protection issues would not have hampered an independent study.
Pfeiffer has said the bishops had wanted to change previously agreed guidelines for the project to include a final veto over publishing its results, which he could not accept.
Norbert Denef, a spokesman for the Netzwerk B group for victims of sexual abuse said the German Catholic Church's action showed it remained unable to accept responsibility for clerical sexual abuse.
He urged politicians to make reporting and prosecuting abuse cases a legal obligation.
About 180,000 Catholics left the German church in 2010 in protest over the scandal, a 40 percent jump over the previous year.
Leutheusser-Schnarrenberger said an independent study was needed to discover whether there were "structures in the Catholic Church that facilitated sexual abuse and what we can do to prevent it in the future." (Reporting by Alexandra Hudson; Editing by Jon Boyle)