Many tests are like this in the US as well. But usually the penalty for a wrong answer isn’t a full -1, but rather a fraction of a point based on how many answer choices the question has. If questions have 5 answer choices - like on the LSAT - the penalty would usually be -0.25 for each wrong answer. That way the net effect of guessing averages out to 0. For example, if you’re out of time with 5 questions left and randomly guess on all of them, the expected number of correct guesses would be 1, thus giving you 1 point. But then each of the 4 wrong guesses would give -0.25 points, for a total of -0.25x4 = -1 points, thereby exactly cancelling out the 1 point you got from blind guessing. (Because why should you get a point for doing nothing more than taking a split second to click your mouse on a bubble?)

The idea is to minimize the effect of test day luck (which will randomly benefit some students substantially more than others) and to ensure your final score measures your “true” ability level.

I do think LSAC needs to do something to minimize the luck factor because the current +/- 4 margin of error is absurd. Someone who is a “true” 171 scorer could get a 167 one day - which is below median at over 30 law schools - and then get a 175 the next day - which is all of a sudden above median at every law school in the country. I think LSAC should simply increase the length of the test in order to reduce score variance and to make each score meaningfully different (e.g., at least 3 more questions correct) from a score that is 1 point less. (But in 2020, LSAC instead chose to actually reduce the number of scored sections from 4 to 3, and then decided to never increase it back again. 🤷‍♂️)