Is it sinful to do non-manual clerical work on Sundays? such as using the time in the day to do reports?

Devoting the day to religious reading and such spiritual activity is by far preferable.  But so long as it does not interfere with your obligation to attend Mass, it is not sinful as it is not servile work.  Manual-labor/servile work would be sinful.

May I ask where this distinction comes from?

So, for instance, someone working in an office, as a clerk, a lawyer, writen, IT consultant, secretary.. could literally work on Sunday?

May I ask where this distinction comes from?

So, for instance, someone working in an office, as a clerk, a lawyer, writen, IT consultant, secretary.. could literally work on Sunday?

We learnt in our catechisms that it is sinful to do "unnecessary servile work" on Sundays. Nursing the sick in a hospital setting would not be regarded as unnecessary. I understand that servile work is work done by an employee for money. But the OP seems to be suggesting he is doing work for himself. I believe OHCA gave the correct response.

Baltimore Catechism No. 3 - Lesson 32

Q. 1252. What is forbidden by the third Commandment?

A. The third Commandment forbids all unnecessary servile work and whatever else may hinder the due observance of the Lord's day.

http://www.ourladyswarriors.org/faith/bc3-32.htm

So what would housework be considered?  I have tried to avoid all housework on Sundays.

Cleaning, laundry, and such would generally be considered servile work.

Quote from: 2Vermont

So what would housework be considered?  I have tried to avoid all housework on Sundays.

Cleaning, laundry, and such would generally be considered servile work.

I am curious about laundry because technically, other than folding the clothes, there is no work really since the machines do it all for us now.

Quote from: 2Vermont

Quote from: OHCA

Quote from: 2Vermont

So what would housework be considered?  I have tried to avoid all housework on Sundays.

Cleaning, laundry, and such would generally be considered servile work.

I am curious about laundry because technically, other than folding the clothes, there is no work really since the machines do it all for us now.

Good point--I was thinking the same thing about taking 90 seconds to put a load of dishes in a dishwasher.  A lot of tasks are automated that used to be labor intensive.

Oh shoot...and this is exactly what I did today (well, unloaded).  Perhaps these are examples of letter vs spirit of the law?

It all depends whether you're rich or poor. The majority of the world is poor and laundry is still hard work for most of the world.

Understood.  

Is it sinful to do non-manual clerical work on Sundays? such as using the time in the day to do reports?

Well it depends on the reports, I guess.  It is not only servile works that are prohibited, but judicial acts and commercial occupation. So reports done for your occupation would likely be prohibited unless they are necessary. You probably shouldn't execute legal docuмents or purchase property on Sundays and Holy Days.

Another distinction is that the phrase "servile works" is not perfectly synonymous with "manual labor" as it is popularly understood (i.e. physically demanding work).  In fact, Aquinas classifies worship of God as a servile work; one which is obligatory on Sundays and Holy Days. The particular definition is found in whom the servile work is meant to serve (God or man).

A further distinction is whether or not the work is "necessary." It is never permitted to do unnecessary servile work on Sundays and Holy Days.  

So, to sum up, if the reports are for your commercial occupation you probably shouldn't do it unless it is absolutely necessary.  As in, you found out Saturday night they are due at 8am Monday.

If they are for personal use (i.e. you are working on your household budget), I would still avoid it because I don't think accounting would be considered a "liberal work."

Years ago, I was designing our home for construction and architectural drawing is considered by Jone (Moral Theology) to be a liberal work.  Even then, Jone warns that a liberal work can become a preoccupation and therefore take away from the purpose of rendering what is owed to God on Sundays and Holy Days.