A Brief Legal History of Time: Part One of Two

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This is the first of a two-part article discussing the world of litigation, timestamps and metadata. It is a twilight zone of litigation where everything—and nothing—makes sense; where time zones, epochs and obscure digital formats mark the dividing line between critical insight and falling prey to the unexpected complexity of the simplest of questions: ‘When?’

‘You are about to enter another dimension, a dimension not only of sight and sound but of mind. A journey into a wondrous land of imagination. Next stop, the Twilight Zone!’

By Dan Regard and Charlie Platt

The clock ticks past midnight. It's late and the documents you've been reviewing for the past several hours have all blurred together. You pull up a key email for what seems like the hundredth time this evening and, rubbing your eyes, you stare at it, knowing you've read it a dozen times already but feeling that somehow an important piece of the litigation puzzle is buried there.

As your eyes start to glaze, it hits you. Excitement washes away exhaustion, you pull up another email and another. One of the emails appears to be part of a chain, but according to the date and timestamps, it was sent two hours before the first part of the chain was received.

On another, one of the key witnesses seems to be sending email at highly unusual hours, but review of the content appears to indicate normal business hours.

Upon further scrutiny, you discover that the email record conflicts with the text message record and the telephone call records. Calendar entries titled, ‘Friday Afternoon Project Status Update,’ appear to be consistently scheduled for the morning.

How concerned should you be? Are these times and dates correct? If not, where did they go wrong and who altered them? If they are incorrect, what are the correct times and dates and how do they change your arguments?

Time and date values can prove tricky: they can easily be interpreted incorrectly, and when that occurs, they have the potential for negative consequences. Depending on the case, a few hours' difference on a critical email or document can easily make the difference between litigating and bringing opposing counsel to the settlement table.

Order Versus Chaos

The universe is a messy place, and despite our best efforts to fit it into tidy little buckets, it simply refuses to comply. Physics tells us that the chair you're sitting on is mostly empty space, and yet it works perfectly well as a chair. Historians tell us that it should be impossible to build Stonehenge with the technology of that time, and yet there it stands. We are all taught that it takes 365 days for the Earth to orbit the sun and 24 hours for it to complete a single rotation, but that isn't necessarily the whole truth.

One area where we expect logic, order and consistency—but reality proves exceptionally chaotic—is time. Ever since the dawn of civilization, we have attempted to measure and classify time. From Stonehenge to Incan calendars to atomic clocks, we categorize our existence into years, our years into seasons, seasons into months, months into days and days into hours, minutes and seconds. We group time into centuries, eras, millennia and eons, and break it down into milliseconds, microseconds, nanoseconds (one billionth of a second) and beyond.

As with other systems of measure, our methods of time measurement have grown more complex as we've developed a need for greater precision.

How Many Days are in a Year?

The Egyptians are credited with the introduction of the 365-day calendar. Prior to that, calendars were commonly based on 360-day years broken down into 12 months of 30 days each. Such calendars were based on the lunar cycle, with the full moon coinciding with the middle of the month. As civilization became increasingly agrarian, such calendars became less useful as they would fall out of synchronization with the seasons, with spring months eventually shifting to occur in the winter. This made the calendar ineffective for agricultural planning purposes, such as determining when to plant and harvest crops. To correct for this, many civilizations would insert leap months to periodically catch the calendars back up to the seasons.

Although the Egyptians were correct and 365 days is more accurate than 360 days, it still isn't quite right. A year is closer to 3651/4 days and every four years we add a leap day to account for this discrepancy.

But even that isn't quite correct, so every 100 years we skip adding a leap day (unless the year is divisible by 400, in which case, we do).

To compound this complexity, it turns out a day isn't actually 24 hours long and every so often we have to add in a leap second. In fact, a day in 2015 was about 1.7 milliseconds longer than a day was in 1915 (Dennis D. McCarthy, 2009, p. 232), so not only are days not 24 hours long, but they aren't even consistently inconsistent.

Time Zones and Trains

Fast forward from ancient Egypt to the late 19th century in the United States. The prevailing method for keeping time was ‘solar time’, with local time based on noon coinciding with the sun being directly overhead. This generally wasn't a problem—until the trains arrived.

Trains opened up the country, allowing people to travel rapidly between cities; so rapidly that the combination of train travel and solar time led to passengers setting their watches in New York and, upon arriving in Philadelphia, finding that their watches were no longer correctly reporting the local time.1

1 This was particularly troublesome when various railway companies kept timetables according to their own home office. A traveler going from Washington, D.C. to Boston might have to change his watch four times or else show a discrepancy of 24 minutes. Bianculli, Anthony J., Iron Rails in the Garden State: Tales of New Jersey Railroading (2008), p. 94.

This lack of consistency between cities grew increasingly problematic, so on October 1, 1884, the International Meridian Conference met in Washington, D.C. and established Greenwich Mean Time (GMT) as a standard. As a result of this conference, and the adoption of GMT, the time zones we know and use today evolved.

This wasn't the only occasion that our means of timekeeping failed to keep pace with evolving technology. Advances in timekeeping, specifically the atomic clock, led to the creation of Coordinated Universal Time (UTC) by the International Radio Consultative Committee in 1960.

UTC linked the universal clock to the atomic clock, allowed for the introduction of leap seconds and, most importantly, provided a standard notation for representing time zones, such as ‘UTC -0500’ for Eastern Standard Time (EST). And this wouldn't be the last time that timekeeping was forced to evolve to meet advances in other technologies.

Relativity and GPS

Consider a modern example of evolving technology and the increasing need for accuracy: the Global Positioning System (GPS). We rely on GPS every day—on our phones and in our cars—to know where we are and tell us how to get where we want to go. Without proper understanding of time and the means of calculating it accurately, GPS would be an impossibility.

The system relies upon hyper-accurate clocks, clocks that must be accurate to within nanoseconds. These clocks reside in satellites travelling at close to 8,700 m.p.h. and orbiting at an altitude of roughly 12,500 miles above the earth. According to Einstein, such clocks fall prey to both the Special Theory of Relativity and the General Theory of Relativity.

Under the Special Theory, speed affects time. The faster you go, the slower time elapses.

Under the General Theory, gravity affects time. The stronger the force of gravity, the slower time elapses.

Thus, under the Special Theory, the 8,700 m.p.h. speed proves fast enough to make the GPS clocks tick seven microseconds slower per day than ground-based clocks (Pogge, 2013).

Alternately, under the General Theory, the 12,500 mile altitude is far enough removed from gravity to make the GPS clocks tick 45 microseconds faster per day (Pogge, 2013). The net effect is that over the period of a day, the satellite's clocks are 38 microseconds faster than ground-based clocks.

While this may sound inconsequential, GPS requires nanosecond accuracy. Thirty-eight microseconds is 38,000 nanoseconds, and would cause GPS to be off by over five miles after only a single day and the effect would compound each day thereafter.

The system would be useless after only a few hours of operation. Just as we saw with the arrival of the railroads, where we started moving fast enough and far enough to show the limitations of our timekeeping, there is a modern parallel with GPS.

As our communications get faster and our systems increasingly integrate with each other, the world gets conceptually smaller and inadequacies begin to appear in our timekeeping technology. Yet we rely on time and date values regularly in litigation: Who knew what—and when did they know it; when was the email sent; when did the stock trade occur; where was the defendant at a specific time? All of these questions are based on time and location and, increasingly, that location is reported via GPS—which is itself reliant upon accurate timekeeping.

Time is Relative

And so we come to the problem of time as it applies to litigation. A primary source of confusion regarding time in litigation stems from the need to represent time as both a relative value (local time) and an absolute value (universal time). We use local time to understand events as they unfold for a specific individual, e.g., ‘When did plaintiff receive the email?’

When asking this question, we're not interested in what time it was in Greenwich or Tokyo or Hong Kong, but rather what time it was locally for plaintiff.

Conversely, we use universal time to understand how events in different time zones relate to each other. Multiple events occurring in different time zones can be converted to UTC so that a proper sequence of events can be observed.

To complicate this, there are presently 41 time zones in effect around the globe. There are instances where two time zones exist within a single city. There are instances of half-hour time zones (e.g., Australian Central Standard Time \ACST\, which is UTC +0930). There are even instances of quarter-hour time zones (e.g., Nepal Time \NPT\, which is UTC +0545).

And, in what would seem to be a complete defiance of logic, there are instances where today, tomorrow and yesterday are all occurring at the same time. This is owing to the oddity that time zones span a total period of 26 hours.

Christmas Island is 14 hours ahead of UTC, while Howland and Baker islands are 12 hours behind. This means that three people having a hypothetical phone conversation could actually be talking on three different dates, the first at 11:00 p.m. Monday, January 1 on Baker Island; the second at 11:00 a.m. Tuesday, January 2 in Greenwich, England; and the third at 1:00 a.m. Wednesday, January 3 on Christmas Island. From a local time viewpoint for each individual, this single conversation occurs on three completely different days. Conversely, from a universal time viewpoint, the conversation is a single event.

If later asked when the conversation took place, one individual might say late at night on Monday; another could disagree and say it was very early morning on Wednesday; and the third, disagreeing altogether, would say it was in the middle of the day on Tuesday. The important thing is that all three would be correct.

Coming In Part II

Time and date keeping has enjoyed a varied past and in the second and final part of article, to be published in the Jan. 21 issue of DDEE, we will discuss how this variability in time and date keeping impacts litigation and identify some of the assumptions, pitfalls and methods used when representing dates and times in litigation. We will also identify issues you should be aware of, when you should be concerned, and what can be done when there is a problem.

Complications of Time Zones and Timestamps


• 41 time zones on Earth (+14 UTC to -12 UTC) that change over time;
• 13 current different methods or dates for Daylight Savings Time (DST) that change over time;
• 5 different DST offsets (20, 30, 40, 60 or 120 minutes);
• 15 different major computer epochs;
• Multiple measurement increments for some epochs;
• Multiple storage formats;
• Varying degrees of precision;
• One document may commingle methods, formats, epochs, and DST


Dan Regard, the co-founder and CEO of iDiscovery Solutions, is an electronic discovery and computer science consultant with 25 years experience in consulting to legal and corporate entities. Mr. Regard is a member of the Sedona Conference WG1 and WG6, as well as a board member of Georgetown Advanced Institute for e-Discovery.

Charlie Platt, a Senior Managing Consultant at iDiscovery Solutions, has over 25 years experience consulting with corporations and clients on information systems development, infrastructure and analysis, digital forensics, cybersecurity and incident response, database administration, eDiscovery cases, software analysis and development, and project management. Mr. Platt is a Certified Ethical Hacker, a Microsoft Certified DBA, and holds certifications in C/C++, Infrastructure and Networking.

Works Cited

Dennis D. McCarthy, K. P. (2009). Time: From Earth Rotation to Atomic Physics. Weinheim, Germany: John Wiley & Sons. Pogge, R. W. (2013, April 10).


Real-World Relativity: The GPS Navigation System. Retrieved September 30, 2015, from Ohio State University: Astronomy 162: http://www.astronomy.ohio-state.edu/~pogge/Ast162/Unit5/gps.html Various. (2015, September 24).



Coordinated Universal Time. Retrieved from Wikipedia: https://en.wikipedia.org/wiki/Coordinated_Universal_Time Various. (2015, August 23).



List of Time Zone offsets. Retrieved from Wikipedia: https://en.wikipedia.org/wiki/List_of_UTC_time_offsets


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