On the Same Page: Penalizing Test-takers who Exceed the Allotted Time

The following is a possible way to construct a penalty system that increases fairness and reduces arbitrariness. The specific numbers are not the key ideas of this article: the methods of arriving at them are the real focus. Because the question “How much of this good thing is enough?” cannot be answered scientifically, the specific numbers have to be decided upon by an authority.

One way to construct a penalty system for students who exceed the allotted testing time:

Simplifying assumptions:

A typical unit exam is allotted 75 min.
The average score on unit exams is about 65%.
Unit exams are composed of four-option multiple-choice items, so even a student who purely guesses will score 25% (on average).

Therefore, an average student will earn (65% - 25%) / 75 min = 40% / 75 min = 0.5 % per minute.
Hence, in order to offset gains from exceeding the time-allotment, the penalty should be at least 0.5% per minute.
A penalty of 1% per minute adds a 0.5% per minute deterrent, which is easily understood, and seems fair (is not draconian).
A further deterrent is that if a student exceeds the time-allotment by 30 min, the exam is forfeited. After 30 min, a student should be well aware that they have exceeded their time allotment. The idea of ½ hour is easily understood and seems reasonable.
Students who write in the test room are given a 10 min grace period. This is justified since they need to keep track of their writing-time on their own and some mental energy is wasted while clock-watching.

Advantages of implementing a penalty system such as the one presented above:

A penalty, thoughtfully implemented, can act to restore fairness by equalizing student marks (to some extent). This makes students’ marks from all modes more comparable and helps the course map to function as intended.
Students will know that they are being treated in approximately the same manner (this increases the perception of fairness because arbitrariness is reduced).
Some deterrent is justified because fewer students (presumably) will try to stretch the rules hoping that no one notices. A deterrent effect is justified to the extent that the deterrent increases fairness and decreases arbitrariness.
This model is not punitive, i.e., does not punish for the sake of punishing as a kind of revenge on behalf of the innocent. Perhaps one could argue that a punishment can engender respect from those who disrespect a policy, but this is quite dubious.

Disadvantages of implementing a penalty system:

The more policies we develop, the more time we need to spend explaining them. Our student handbook starts to become a policy manual.
The more policies we develop, the more energy we need to spend policing the policy.
The police might need to be policed.
Policies become the first and most important thing we communicate, especially in ATOL, so students know the landscape they need to navigate. In ATOL, we do not want students to be surprised by what could be perceived as “gotchas.”
Sometimes any gains one hopes to achieve by implementing a system are negated by the effort required to police the system and the ill will engendered by the things police are sometimes compelled (by law) to do: confiscate and fine.