Task: Question Answering
Input (English): Passage: In the 1830s an aboriginal is charged with the spearing of a white settler, but was about to be released by the Captain convinced of his innocence after questioning him. But, during a party that night, a drunken officer shoots and kills the prisoner, and is charged with his murder.
Thomas Morland, the acting Attorney General, is sent to Newcastle to investigate.
Captain Alcot wishes to keep on the good side of the land-hungry Carlton so they attempt to defend the drunken lieutenant who has shot a native. Neither believe the prisoner Jacko had anything to do with the murder of a white settler, since he was captured 60 miles away from the crime. So they bribe Sergeant Constantine, who arrested Jacko, into saying that the place of arrest was close to Newcastle.
At a trial in Sydney, the lieutenant is charged with murder by the Acting Attorney-General. False testimony by Constantine brings a verdict of not guilty; but the playwright makes it clear that it is as much a victory as a defeat—"people will have second thoughts" about molesting aborigines after this. 
Question: What are the last names of the people who bribe someone?
Output (English): Carlton.