Infraction Types listed have a red X so would expect to be able to delete, however, after clicking on the X, a pink "Error" banner appears. The reason for this is the Infraction Type has a Consequence tied to it.
This has been determined to be a defect as there should be a padlock icon to indicate the Infraction Type is in use and cannot be deleted.
Steps to Duplicate
Navigate to onRecord > Settings > Conduct
On the Infractions Type tab, click the red X beside the Infraction Type
Click the Confirm button in the confirmation message that displays