What does "up to 36 points" mean?

"Added up" is an idiom meaning "totalled". Each of Skilling's previous convictions are given a number of points. Adding them together gave a total of 36 points.

Teacher: Johnny, add up these numbers: four, six, three, seven.
Johnny: twenty!
Teacher: correct!

Thanks.
But my problem is the meaning of the word "point" in laws.

Used here a point is a unit of measurement: when calculating the sentence to be given, a judge arrives at scores for two things: the previous criminal history of the offender, and the seriousness of the offence or offences in the present case. The government has created tables in which offences are given points. These are added together. Here is an imaginary table of points to be awarded for offences:

Theft of less than $500: 1 point
Theft of $500 to $5000: 2 points
Theft of over $5000: 10 points
Assault causing slight injury: 1 point
Assault causing injury requiring hospital stay: 5 points
Robbery without weapon: 10 points
Robbery with weapon: 20 points

One point represents (in my imaginary system) 6 months in prison.

Here's a long, but accurate description of how the system is suppposed to work.
It was designed to give judges a measurement to guide them on how many months or years of prison was appropriate to the person and the crime(s) committed.

http://www.leelofland.com/wordpress/a-federal-offense-how-much-time-will-you-serve/

I hope this helps.

Joe( )Nation