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The purpose of this informational memorandum is to provide law enforcement users a standard procedure for handling, securing and protecting video information so that maximum investigative utility may be obtained from it, the odds of conviction can be enhanced and investigator time and effort minimized.

This document will address retrieving evidence from closed circuit television video recording systems, which may employ time lapse recorders, and the steps necessary to obtain the information available from these systems. There are five major steps which will be covered in detail:

1. Determine if there is a videotape
- Cameras
- Recorders

2. Stop the Recorder
- Seize tapes as evidence
- Check for ancillary recorders

3. Document the video system's physical relation to the crime scene
- Camera views
- Timing

4. Protect the video tape

- Break off the Write Protect Tab
- Make a copy
- Store the original -- Under Chain of Evidence
- Analyze the copy

5. Seek technical assistance help if problems occur

1. Determining If There Is A Video Tape

One of the first questions asked by officers responding to the crime scene should be, "Is there a video tape at the incident?, Where are the cameras?, Where are the recorders?"

2. Stop the Recorder

Often recorders continue after a crime has been committed, therefore, one of the first things to be done at the crime scene is to stop the recorders to avoid accidentally recording over the information you need. Next, confiscate the tapes immediately; put them into a chain-of-evidence before someone edits them.

When handling videotape evidence, first stop the recorder but do not eject the tape. It is important to take the time at this point to be sure you know how to stop and eject the tape without accidentally restarting the recording. Next, note the time on the recorder and simultaneously note the time on your watch. Do this to the highest accuracy possible, i.e., to the second. Often the time on your watch and the time on the recorder will not be the same. Therefore, this time discrepancy may be needed and may be important in subsequent analysis. Also note any time differences with any other clocks in the vicinity that may be noticed by witnesses. Next, note the position counter on the tape recorder. Times on recorders are notoriously incorrect -- sometimes they have been off by hours. Rewind the tape and note the position of the counter again. The difference between the position of the counter number prior to rewinding and after rewinding will facilitate the repositioning and analysis of the tape later. Now carefully eject the tape.

Next, write down the information about the recorder. Note the manufacturer, the model, the time-lapse mode and any other settings the recorder was in.

In addition to locating video equipment at the scene of a crime, look for additional video that may have a view of a crime (that might be down the street from the scene) which may contain, for instance, the car driving away. For instance, when there is a crime at a mall, there may be convenience stores or bank ATM videos that see suspects entering or leaving the crime area. In addition, suspects may have been in other nearby locations, for instance streets used for entry or exit routes. Also, it may be useful to look at earlier tape recordings than when the crime occurred; sometimes suspects may have visited the location prior to the crime. If ancillary tapes are located, these same procedures apply to them.

3. Document the Video System'(s) Physical Relationship to the Crime Scene

Write down the location of the cameras and their views in the report or diagram or photograph this data. Additionally, size measurements (height, depth, width) of reference objects in the scene should be measured so that they can be utilized to determine physical dimensions of other things such as the height of a suspect.

4. Protect the Tape

Most tapes have a "write protect" tab. Break off this tab so that it can't be inadvertently recorded over.

Now that you have a tape, what is the best procedure? Although it is often compelling, do not play the tape; take it somewhere to be copied and play only the copy, thereby saving the original for professional analysis. The reason this procedure is recommended is that often the tapes are old and playing a tape does degrade it. If you have gone to the trouble to collect this tape as evidence, it implies prudent handling. Pausing or slow motion viewing degrades the tape more. In addition, time lapse video may not be viewable on ordinary tape recorders. From a video surveillance analysts perspective, the most common errors are: 1) A tape has been paused on the critical image for a long time for study and is thereby ruined for forensic analysis; 2) Only a portion of a tape is analyzed and there is additional or corroborating information on earlier parts of a tape.

Make certain that the original tape is secured as evidence and stored where it will not be damaged by magnetic fields such as electric motors, solenoids, and magnetic metal detectors. Also, take care that the tape does not overheat, e.g., do not leave in car in sunlight. Store in cool dry location. Excessive heat and humidity will cause deterioration.

5. Seek Technical Assistance if Problems Occur

Any of the National Law Enforcement & Corrections Technology Centers may be contacted for advice and assistance if needed. Also, the FBI has the capability to do video tape analysis and many of the larger criminalistics laboratories around the nation are available for consultation, guidance and assistance.

What can be expected from the analysis of video recordings? They can show the crime scene, they often provide a synopsis of a crime and/or the description of the crime scene that would be hard to describe in words or testimony alone. The video itself is physical evidence similar to a photograph. It may provide images of actions, statements or other physical evidence that may be part of a crime (hand gun, rifle, knife, car) and it provides a format for which associate evidence may be used to establish connection or association between a crime scene and an individual. For instance, the car at a crime scene compared with a car of a suspect, or shoes observed on a person on the video of a crime compared with shoes of the suspect. Not only might it show a connection between a suspect and a crime, it might provide an alibi for innocent individuals. In addition, video (even stop-action video) can be used to show action in a fashion from which intent may be inferred. For instance, motion video of a person can reveal vigor of actions (pace), emotions or other outward indicators of a persons state of mind, not simply identity as a stop-action photograph might do.

Preparation and Planning are the keys to success in any endeavor and certainly this is true in gathering technical evidence from video surveillance equipment. Well prepared officers knowledgeable in the steps required can make the best use of a powerful tool. It is the hope of the NLECTC that the information contained in this document can assist in this endeavor.