The Phoenix Police Dept. had several rapes on their hands with similar characteristics at this point and suspected a serial rapist was at work.
September 22, 2005. (48 hours) Phoenix Police detectives requested the Phoenix Crime Laboratory perform analysis on ALL items in the sex kit. Both the above mentioned left and right breast swabs are in this kit and have been preserved under a chain of custody since their collection.
October 9, 2005. (2 1/2 weeks) The Crime Lab identifies biological material (nucleated cells) present that would be suitable for DNA testing on both the left AND the right breast swabs, as well as the labia and vulva swabs --- areas where the rapist had also licked.
The right breast swab was ordered tested by the Crime Lab. But inexplicably, the left breast swab was not tested and instead was placed in a freezer for storage untested.
Why some samples were ordered tested and not others is not explained. This was a conscious decision because all other specimens are ordered to be stored instead of tested.
November 23, 2005. (Two months) The right breast swab is finally tested by the Phoenix Crime Lab. The results are marked inconclusive. Inconclusive for non-victim DNA or inconclusive for a sufficient number of distinguishing markers?
The test being performed is referred to as an STR ("star") test, and looks for matching "short tandem repeats."
[adapted from Wikipedia] A short tandem repeat (STR) in DNA occurs when a pattern of two or more nucleotides are repeated AND the repeated sequences are directly adjacent to each other and are repeated a unique number of times per individual.
The STRs in use today for forensic analysis are all tetra- or penta-nucleotide repeats (4 or 5 nucleotides long repeated), as these give a high degree of error-free data while being robust enough to survive degradation in non-ideal conditions.
CODIS (Combined DNA Index System = CODIS, the FBI national DNA forensics database) uses 13 STR markers each located on different human chromosomes, plus AMEL marker which is used to determine the sex of the DNA donor being tested (markers designated):
The analysis is performed by extracting nuclear DNA from the cells of a forensic sample of interest, then amplifying specific regions of the extracted DNA by means of a polymerase chain reaction. Once these sequences have been amplified, they are resolved through capillary electrophoresis, which will allow the analyst to determine the number of repeats of the STR sequence in question are present.
So what is going on here? Why didn't all of the samples get tested?
Ground was broken on the new Phoenix Police Crime Laboratory in October of 2004. It was completed and open for business in 2005. Clearly their CODIS data for 2004 and 2005 are essentially identical so they were working as a testing laboratory somewhere before their new lab was completed. So experience should not be an excuse.
Overworked? Overburdened with samples?
It's mission statement is "The central purpose for the existence of the Phoenix Police Department Crime Laboratory is to provide the highest quality forensic services and scientific technical support to the criminal justice community. Our vision is to make Phoenix the safest major city by providing excellence in forensic science analysis."
From December 12, 2005 through June 26, 2006 (three to nine months) eight people were murdered. It is believed their murderer may be linked to prior rapes that have occurred in the same area under similar circumstances.
During this time on February 16, 2006 (five months) Phoenix Police Detectives request the Phoenix crime lab again test ALL of the biological material from the Alejandra rape case for DNA because of “[t]he magnitude of all the possible related cases and the number of victims....”
March 1, 2006, (5 1/2 months) the Phoenix Crime Lab extracts 18 samples for DNA testing. No results are presented, so were DNA tests done?
August 24, 2006 (11 months) After months of begging and threats detectives within the Phoenix Police Department are finally given permission to request the Arizona Department of Public Safety's (DPS) Forensic Laboratory DNA test all of the Alejandra rape specimens, including both the right and left breast swabs. The request they make is for a more specific y-STR ("why-star") DNA test, is a STR test that is specific for males. But the markers are confined to the single Y chromosome normally only found in males. The advantage in rape cases is obvious...only the rapist's DNA should react as long as the victim is female.
y-STR:: The DPS uses 16 y-STR markers each located on different areas of the human Y-chromosome (male chromosome):
Y GATA H4
Because only males have a Y chromosome, female DNA does not interfere with Y chromosomal testing. Unlike STR testing, y-STRs are not unique to each individual. The Y chromosome and therefor, the y-STRs are inherited from their fathers, meaning that all paternally related males will have the same y-STR profile.
The DPS not only runs their y-STR test on the right AND the left breast, but labial and circumoral (surrounding the mouth) samples as well. Their test examines matches at 16 different locations on the Y chromosome. Profile matches are expected to occur no less than 1 in 333 times in the African-American population (such as Mark Goudeau). Not a huge number in random probability, but fairly big.
This produced matches from the right breast and labial samples consistent with Mark Goudeau's on file in the offender database, meaning they could not exclude him at the time. Additionally they picked up the rapist's DNA on the inside and outside of the victim's shirt, and outside her purse that were similarly consistent with Mark Goudaeu.
They also ran the (non-y) STR test as well on the left breast that the Phoenix Crime Lab had not tested. This separate test STR has a hit on the stored left breast sample consistent with the victim, her sister and Marc Goudeau. They also tested the left breast sample with their y-STR test producing a similar match to Mr. Goudeau. The combined odds of a random match existing from both tests is over 360 trillion in the African American population. The previously untested left breast sample nails it. [PS: I have my doubts about this odds claim. I doubt it is much over 1 in a billion and would love to see the statistical calculations.]
Further, Mr. Mark Goudeau's DNA sample was on file and available for comparison at the time of the testing.
Extensive testing report by DPS can be downloaded here. I should note, even here the actual test results are not present.
Why the Phoenix Crime Lab failed to yield conclusive forensic STR results on the right breast is unknown. Degraded sample seems less likely since the DPS successfully created a profile in their y-STR test. It is possible they lost at some point the DNA during sample extraction and concentration or that phenol contamination associated with the extraction process remained behind undetected to contaminate and prevent the test reaction from working. Additionally, the rapist rubbed dirt on Alejandra's breasts in an effort to thwart DNA sampling. Soil contaminates are known to inhibit the STR PCR step unless they are well removed from the DNA. Since the actual test results are not present its failure is impossible to evaluate. In fact, none of the actual test results are available...only a final interpretive result.
But the left breast -- which was positive by both STR and y-STR in the DPS laboratory's hands -- was not tested despite repeated demands by Phoenix Police that all specimens collected be tested as a priority, and compatible biological material was noted as being present for testing by the Phoenix Crime Lab scientists.
September 11, 2006 (one week shy of one year of terror the community has been held hostage by a serial killer/rapist) the DPS Forensics Lab reports the DNA test referred to as STR ("star") DNA was an State's DNA Indexing System (SDIS) that feeds into CODIS match to suspect Mark Goudeau with the previously untested, but stored, left breast swabs. [It would be more accurate to say the DNA test did not rule Goudeau out as a suspect. Also note, the actual match data is not present.]
Families of the murder victims are rightfully angry their loved ones were not protected from this serial killer when the evidence linking him to rape victims was already at hand before any killing took place. As to why these samples were not tested by the Phoenix Crime Lab after being requested at least twice to do so, hopefully depositions will bring the reasons out.
An attorney for three of the murder victim's families, Marc Victor, who has brought suit on behalf of these families against the City of Phoenix says he is outraged that the police were hampered in their investigation by the failure to get their evidence tested in a timely and apparently accurate manner by the Phoenix crime lab. And that it is unconscionable that it took so long for the specimens to finally be transfered from the Phoenix Crime Lab for testing at an alternate nearby DPS forensic facility.
Powell Gammill is the Senior Editor for Freedom's Phoenix, a current news server for the planet.
In his past life he managed microbiology and molecular biology laboratories for government and private industry. He organized, trained and supervised bench scientists who had to perform laboratory and DNA testing on chain of custody samples for various police departments and other government entities throughout the state of Arizona related to bioterrorism detection. At the time his labs and personnel were highly regarded for being advanced and for their proficiency and efficiency.