The most secure area of a Texas prison is death row. That's what an investigator assigned to prosecute prison crime testified in a Leon County courtroom Tuesday. The jury is deciding if Huntsville prison inmate Jerry Martin should be put to death for the murder of prison guard Susan Canfield, or if Martin should receive life without parole.

Walker County District Attorney David Weeks asked the jury to consider if Martin would be a future threat, or if there was anything that mitigated the death penalty in this case.

Stephen Rogers, a committee member with the Texas prison State Classification Office was called to testify for the prosecution. He said offenders who are assigned life without parole are automatically assigned a G3 status within the prison. A G3 status falls in the middle of general population inmate statuses. After ten years, Martin would be eligible to move to a less restrictive status, Rogers said. Offenders are classified based on the length of time they are ordered to serve, as well as behavior in prison. An inmate's offense is not a factor in his or her classification Rogers said.

Since Martin and inmate John Falk briefly escaped from Huntsville's Wynne Unit in September 2007, Martin has been living in administrative segregation in prison. Rogers said administrative segregation was considered to be a non punitive classification, but one given to inmates with a high probability of causing a disruption. Inmates who have escaped or attempted escape are often placed there Rogers said. The ultimate purpose of administrative segregation is to separate offenders from the general prison population and keep TDCJ staff members safe, Rogers said.

During questioning of Rogers, defense attorney Billy Carter tried to make the case that if Martin wasn't put to death, he would likely stay in administrative segregation for the rest of his life.

Inmates living in administrative segregation are only allowed to leave their cells for one hour a day, eat and shower by themselves, and may not attend prison church services or go to the library. They leave their cells in handcuffs.

A.P. Merillat, an investigator with the Walker Count Special Prosecution Unit, was also called to testify for the prosecution. The SPU is an extension of the district attorney's office that prosecutes prison crime.

According to Merillat, there have been 78 serious assaults on prison staff members so far this year. Four of those occurred in October, nine occurred in September.

This year, Merillat said 29 convicted capital murderer inmates and 94 inmates who were convicted murderers have been prosecuted for crimes they committed while in prison. During that time, there were 1024 new indictments. When asked if there was any place in TDCJ that was completely safe, Merillat replied "no." He answered the same when asked if there was any place an assault could not happen.

Refering to the same report by the state prison system's Emergency Action Center, Carter pointed out there were 1,800 violent acts last month, and with roughly 155,000 inmates in the system, Carter said that only 1% of the population committed those acts.

Merillat said "every area of the prison system has had some form of criminal activity in it." Saying that inmates had committed murders and even escaped while on administrative segregation. "The most secure area of the prison is death row," said Merillat.

Prosecutors will continue calling witnesses Wednesday. Martin's fate isn't expected to be formally handed over to the jury until early next week.

Martin was serving prison time for four separate charges. The first three stem from an incident that occurred on August 15, 1994. He was convicted of firing at three officers in Collin County, in the Dallas-Fort Worth area and received 10 years for aggravated assault on one of those counts, as well as a 50-year and 40-year sentence for two counts of attempted capital murder.

Martin was indicted until January of 1997, and wasn't convicted until July of that year. He is also serving a 10 year prison sentence for failing to appear in court in October 1995.