The defence team has argued that the trial has been politically motivated.
He is the first former African leader to face such an international tribunal.
He has been accused of arming and controlling the Revolutionary United Front (RUF) rebels during a 10-year campaign of terror conducted largely against civilians.
The RUF became infamous for hacking off the limbs of its victims, and using rape and murder to terrorise the population.
On Friday morning, prosecution counsel Nicholas Koumjian said that Mr Taylor, 62, was an intelligent and charismatic person who could fool some of the people some of the time.
He was counting now on fooling the judges at the war crimes court, he said.
The prosecution statement was followed by defence rebuttals on the final day of hearings.
Judges have now adjourned to consider the verdict, expected in about four months.
On Thursday, the defence team attacked the credibility of some prosecution witnesses.
Funds had been “lavished” on witnesses, the lawyers said.
Mr Taylor’s lawyers have argued that he tried to broker peace in Sierra Leone at the request of regional powers.
He has been accused of selling “blood diamonds” for the rebels, in return for supplying them with weapons.
The prosecution was trying to establish a link between Mr Taylor and a number of uncut diamonds that Miss Campbell said she had been given in South Africa in 1997.
If convicted, Mr Taylor would serve a prison sentence in the UK.
- 1989: Launches rebellion in Liberia
- 1991: RUF rebellion starts in Sierra Leone
- 1995: Peace deal signed
- 1997: Elected president
- 1999: Liberia’s Lurd rebels start insurrection to oust Mr Taylor
- June 2003: Arrest warrant issued
- August 2003: Steps down, flees to Nigeria
- March 2006: Arrested, sent to Sierra Leone
- June 2007: Trial opens in The Hague