By Kristen Johanson

PHILADELPHIA (CBS) — The murder trial for a man accused of dismembering a transgender woman nearly five years ago started this week with the suspect representing himself in court.

Forty-four-year-old Charles Sargent has been charged with murder and abuse of corpse in the 2013 murder of Diamond Williams, a transgender woman, prosecutors say Sargent picked up for sex, and eventually killed.

A crime scene investigator took the stand as prosecutors pulled pictures of the severed body found in an overgrown lot near Sedgley Avenue and York Street.

Police say blood and tarps were found at Sargent’s house, where they say he mutilated the body with a screwdriver and knife.

The victim’s pelvis was found in the Schuylkill River.

Court documents show Sargent’s previous defense attorney questioned Sargent’s mental state, but the court ruled him competent after the defendant denied to see doctors.

A doctor with the city’s medical examiner also testified, with homicide detectives expected to testify on Thursday.