To differentiate between procedural and substantive law, courts look at whether the rule in question essentially affects the outcome of the litigation. Procedural laws are deemed those that solely dictate the method of enforcing rights. If a rule influences the litigant’s ability to secure relief or defenses available, it is likely substantive.
For example: A statute requiring litigants to notify defendants within a certain timeframe before filing suit is procedural; however, if a statute reduces the amount of recoverable damages, it’s substantive as it affects the extent of recovery.