Sunday, August 27, 2006

Additional sources of audio and video evidence

I came across this news article today that illustrates one of the other sources of audio and video evidence used in legal proceedings. In this case the source was from recordings made during the interview of a suspect (now defendent) and it was introduced into his trial to help establish his state of mind - in other words, whether he was "legally insane" at the time of the murder.

As you can now see, audio and video evidence is not only obtained from surveillance or recovery (e.g. from the scene of the crime, nearby ATM cameras, etc.). As a matter of fact, in recent years recording of police interviews has become increasingly common throughout the world, so this source of audio and video evidence will also become more common in trials.

Age related hearing loss may also have hereditary component

The BBC reports on work funded by the Royal National Institute for Deaf People:

About 37% of Britons aged 61 to 70 and 60% of those aged 71 to 80 - 6.5m people - have age-related hearing loss.

The Human Mutation study of over 1,200 people found subtle changes in a gene called KCNQ4 were more common in those with age-related hearing problems.

Based on this study, common age related hearing loss appears likely to be due to a combination of environmental (e.g. exposure to loud sounds) and genetic factors. The gene KCNQ4 has previously been linked to a hereditary form of hearing loss that strikes young people, regardless of exposure to loud sounds. This doesn't mean that exposure to loud sounds won't cause hearing loss - it will. Instead, the way I interpret the study, it is more likely that if KCNQ4 is seriously defective then hearing loss strikes early; if it is a defective to a "lesser" extent, then one is more succeptible to age related hearing loss; and, finally, if it is normal, one can still lose hearing due to loud sounds (and maybe through other mechanisms, such as age related degradation of tissues and such in the ear).

Note: The above is my own interpretation and is meant to estimate a trend, based on experience and scientific reasoning, and may not be fully supported by existing data.

Saturday, August 26, 2006

Air traffic control intercepts of Northwest Airlines turnback flight with F-16 escort

Audio recordings (wma format) of conversations between air traffic control and the F-16 escort for Northwest Airlines flight 42 to Mumbai that had to turn back to Schiphol (Netherlands) due to concerns about some passengers. Recordings courtesy of the Frequency Monitoring Centre, the Netherlands. Recording is very intelligible with only a little hiss and occassional louder noise.

(Hat tip: Flight Global) (note: I stumbled across the Flight Global page from a news article but now can't find the original site that got me on the trail).

Wednesday, August 16, 2006

Naps enable additional learning in babies

ScienceDaily reports that psychologists at the University of Arizona have found that naps enabled babies to learn more than ones who didn't take naps. Sleep has been long known to cement memory formation in adults. This sounds like the beginnings of a good excuse for that Sunday nap - "But honey, scientists have shown that it will make me smarter and improve my memory!"

The study was published in the August issue of Psychological Science.

(Hat tip: ScienceDaily)

Tuesday, August 15, 2006

Exhibits from trial of Zacarias Moussaoui

Trial exhibits from prosecution and defense of Zacarias Moussaoui are now available online here. Security camera photos, video clips, emails, transcripts, money transfers, faxes, receipts, and audio clips (just to name a few!) are included. If you want to see how a major terrorist case is assembled, this is a good place to start.

(Hat tip: Chronicles of Max)

The last two months were not kind...

William (Bill) K. Heineman -Washington Post obituary
Bill made important contributions to law enforcement and security over the years, both in government service (FBI) and in industry (Tektron). He was respected, admired, and appreciated by many for his accomplishments as well as his character.

Steven C. Marshall (a.k.a. Stephen St. Croix) - Forbes obituary. (Updated: Mix magazine obituary)
Few people leave a mark in a single industry - Stephen left marks in three different industries - in the movies (Star Wars, Wizard of Oz, and Gone with the Wind), in music (Songs in the Key of Life), and in law enforcement (Intelligent Devices).

Both of them were called from us early and will be missed.

New links and other housekeeping

Finally managed to get around to some housekeeping duties tonight - corrected links to pages that had moved as well as added some new links in the Science, Security, Biometrics, and Politics sections (on the right hand side).

Study to ID a person by texting style

Researchers at the University of Leicester (UK) are undertaking a study to determine if it might be possible to recognize an individual by their texting style. The psychologists involved plan to use linguistic analysis on text submitted by volunteers who will participate over the Internet.

(Hat tip: CNET.CO.UK)

Security camera deployment and operational issues in the USA

Some time ago I posted about the 'evils' of highly compressing security camera images in order to maximize the number of days of footage that could be stored. That post came to mind as I read an article in the Washington Times online edition that talked about camers to be installed in WDC and referenced similar programs in Baltimore, Chicago, and San Francisco. The first quote that caught my eye was about statistics collected from the Baltimore system and it said:
"Generally, the State's Attorney's Office has not found them to be a useful tool to prosecutors," office spokeswoman Margaret Burns said. "They're good for circumstantial evidence, but it definitely isn't evidence we find useful to convict somebody of a crime."
That quote was followed by this one:

"We have not used any footage to resolve a violent-crime case," she said.
Miss Burns said police sometimes misidentify suspects because the cameras produce "grainy" and "blurry" images.
"We have had that happen more than once," she said.

"Why?", you might ask. The things that come immediately to mind are 1) too far away, 2) poor lighting, 3) poor lens/camera, and 4) too much compression. I'd be willing to wager money on it being the latter, at least in large part. I say that based on experience and also on noting what wasn't said - no complaints about live monitoring - as well as an inference I made based on the fact that a security camera helped solve one case even though no image was recorded (which to me says that an operator likely saw something important using the camera).

The entire article is interesting and gives some insight into real-life issues with deploying and operating these systems. Many of these issues are addressable and data like this can help point the way to workable solutions.

Predictors of late talking in toddlers

Science Daily has an article (13 July 2006) on a study by the Telethon Institute for Child Health Research, Curtin University of Technology, and the University of Kansas (USA) on predictors of late talking in toddlers.

The main findings of the study were that 1) roughly 13 percent of children at age two were late talkers; 2) that factors involving mothers' education, income, and such had no significant influence; and 3) that most late talkers had normal language development by age seven.

To read more, see Telethon Institute for Child Health Research.

Hiatus comes to an end

After an array processing conference (SAM 2006, short for Sensor Array and Multi-channel processing), one international business trip, one law enforcement conference (NATIA 2006, where I was a speaker), and a patent filing, I am finally back to blogging. It was a busy few weeks...