On 20-22 July the Prosecution presented the
evidence of five members of the Prosecution who were responsible for the creation of call
sequence tables (CSTs).
The Prosecution explains in court that a CST “presents a chronological and complete sequence of calls
relating to a particular phone number referred to as the target number over a
specified period of time. The CSTs detail each call including the other
telephone number the target number was in contact with; the date and time of
the call; the type of call, either voice or short message service, or SMS; its
duration; information on the handset used by the target number; and cell
information on the cell sector used by the target number at the start of the
call. The CST occasionally also may include information on the cell sector used
at the end of the call, which is referred to as end cell data.”
There are also
CSTs for SMS (text messages), which present the SMS content sent and
received by a phone over a relevant data range in a consistent accessible
format. The SMS CST provides the data and time of the SMS; the other telephone
number involved; the direction of the SMS and its content.
The Chamber, in its decision of 6 May in
relation to call sequence tables, witness statements and the legality of the
transfer of call data records to UNIIIC and the Prosecution, has deferred its
decision on the admissibility of CSTs (and related witness statements) until at
least one witness has testified about the provenance of the call data records
and the production of the CSTs.
Ms. Kei Kamei
The first witness, Ms. Kei Kamei, has been
working as an analyst with the Office of the Prosecutor since 9 November 2009,
and previously worked for UNIIIC. She has personally produced numerous (SMS)
CSTs and coordinated the standardisation of CSTs within the office. Ms. Kamei
gives evidence on the source materials she used to produce the CSTs, which are
(i) files for one particular phone number or interest; and (ii) bulk data for
multiple numbers on a specific day. Ms. Kamei explains the various component
parts of call data records. The Prosecution received this data by making a
request for assistance to the Lebanese telecommunications service provider in
relation to a specific number of interest. The Prosecution requested the bulk
call data records for the period September 2004-December 2005 - which was later
even extended - that is all phone calls made in Lebanon between these dates. Ms.
Kamei further explains the functioning of the SQL database which was used to
analyse the bulk data. Further, for the SMS CSTs only bulk data was used,
although not all content of the SMS messages appeared to be available in the
call data records. In addition, a list with cell tower names received from the
telecommunication companies was used to replace the cell IDs in the CSTs.
Ms. Kamei continues to explain how she created
the CSTs out of the available data, which involved quite some manual handling.
The Judges express their concern as to the accuracy and reliability of the CSTs
produced. Ms. Kamei explains the content of various
CSTs shown to her. The amount of errors located and the validation and peer
review processes are discussed as well.
During cross-examination Mr. Edwards questions
the witness about the creation of her statement, and about spot-checks and
quality control of the CSTs. If another analyst checks the CST, usually that
person would go to the raw source and extract a few, do spot-checks on certain
rows. There was not a formal protocol. No
record was kept of the errors that were found. Ms. Kamei admits that it is
possible that some of the CSTs contain mistakes that were not detected.
Mr. Andrew Donaldson
The next witness, Mr. Donaldson has been a Prosecution analyst since March 2009. He
produced 45 CSTs, and in his statements he describes the components of the
CSTs, as well as the sources, and the creation and double-checking of the CSTs.
Mr. Donaldson would give his work a 9.9 on a scale of 10 regarding accuracy. The
witness estimates that almost all of the CSTs that the Prosecution intends to
rely upon as exhibits have been peer reviewed.
Ms. Helena Habraken
Ms. Habraken is the next analyst of
the Office of the Prosecutor giving testimony about the CSTs. In her statement
of 18 December 2014 she describes having produced 27 CSTs, and she also
describes the work methods and sources of the CSTs. Ms. Habraken states that she thinks that the
CSTs she made are highly accurate representations of the call data records. According
to her, and generally speaking, most errors in the CSTs are formatting errors,
when a number would not be properly displayed or a problem in a date or time
format.
Mr. Lachlan Christie
Mr. Christie also is an analyst with the Office
of the Prosecutor who produced CSTs. He testifies about the same topics as the
previous witnesses. Again his confidence level is high that the CSTs he
produced are accurate representations of the call data records.
Mr. Christian Carnus
Another Prosecution analyst who
produced SMS CSTs, Mr. Carnus describes the method he used to create the SMS
CSTs: the SMS contents records were provided by MTC Touch to the Prosecution in
the form of large text files for multiple numbers. Mr. Carnus queried the data
through the stored procedures in the SQL database and copied the results into
an Excel spreadsheet. Mr. Carnus then formatted the SMS CST. Also Mr. Carnus
was asked about his confidence level and he is very confident that the SMS CSTs
accurately reflect the SQL database. He confirms that the errors he detected
were mainly cosmetic in nature. He also confirms that there was no formal peer
review process. There was no cross-examination by the Defence.
Ms. Nadine Stanford
Ms. Stanford is another Prosecution analyst and
her statement tendered into evidence contains similar evidence as the previous
witnesses.
