Complex sentence: The French secret police and Scotland Yard tried and failed to collect enough evidence to convict Bolo Pasha, but eventually he was convicted of treason with the help of evidence collected by the United States Department of Justice.
Split into simpler sentences: The French secret police and Scotland Yard tried and failed to collect enough evidence to convict Bolo Pasha. Eventually he was convicted of treason with the help of evidence collected by the United States Department of Justice.