Today is April 1, 2011, and therefore April Fool's Day. The question is can Catholics legitimately participate in it without sinning? This is a question which deserves to be addressed because most Catholics do participate, but we must always follow our moral compass, no matter the time of year. The main moral issues brought up in April Fools include lying, and causing harm to others. "Harm" of course can be accomplished in a multitude of ways, and therefore most sins could come under this categorization.
First, let's address lying. Often, April Fools jokes involve convincing someone that something which is actually false is true. For example, we may tell someone something serious has occurred when in fact it hasn't. This will cause a reaction of panic. The panic is quelled when the victim is told the truth. This normally begets a reaction of annoyance, hopefully followed by laughter.
The reverse can be used as well. Rather than negative news, extremely positive (but false) news is given to the victim. For example, they are told they won the lottery, or that they will receive a bonus at work. But then it is revealed that there is in fact, no monetary gain to be had. The subsequent truth causes upset and a feeling of loss to the victim, who will hopefully get over it, and once again laugh.
To find out how serious lying is, let's look at Church sources such as the Bible, the Catechism, and Church documents.
This is what the Catechism states about lying:
2464 The eighth commandment forbids misrepresenting the truth in our relations with others. This moral prescription flows from the vocation of the holy people to bear witness to their God who is the truth and wills the truth. Offenses against the truth express by word or deed a refusal to commit oneself to moral uprightness: they are fundamental infidelities to God and, in this sense, they undermine the foundations of the covenant.
Seems rather clear that we are not to lie. However, can exceptions be made?
Later, the Catechism states:
2484 The gravity of a lie is measured against the nature of the truth it deforms, the circumstances, the intentions of the one who lies, and the harm suffered by its victims. If a lie in itself only constitutes a venial sin, it becomes mortal when it does grave injury to the virtues of justice and charity.
So, the criteria for the seriousness of a lie are 1) the truth it deforms 2) the circumstances 3) the intentions of the one who lies 4) the harm suffered by its victims
Therefore, it seems reasonable that if an April Fools Joke does not deform a major truth, and the intention is to simply cause some laughter, and the harm suffered by the victim is very minor, then it should be permissible. But most of all, I think the circumstances are important (2). People know it is April Fools Day and are expecting to be pranked. Therefore, the circumstances would usually make it okay.
Having said that, if any of the criteria for a serious lie are implemented, I think it could be considered wrong. For example, telling someone something extremely serious, or lying to cause harm or suffering. In those cases, an April Fools lie can go beyond proper Catholic teaching.
But what about other pranks? I think most other pranks must follow proper moral guidelines. If the prank will cause excessive damage, cost, or suffering, it should not be used. How this is determined will depend on the person and the action undertaken.
Here are some guidelines, which I think could be used:
1) The prank cannot cause permanent negative effects
2) The prank cannot involve extremely serious matter, so as to cause excessive panic
3) Once a prank has been performed, it should be revealed soon after the reaction of the victim.
4) The prank cannot be an immediate cause of an excessive reaction of the victim. This can usually be foreseen. For example, it would be imprudent to tell a victim that someone just jumped into the frigid water, thus causing the victim to risk their life attempting to save the fictional jumper by themselves jumping in. Another example would be to indicate to the April Fools victim that their spouse is cheating on them, and provide a false name of a person who is doing it. This may cause irrevocable damage.
5) An April Fools prank cannot place the perpetrator or victim in a situation where the possibility of a grave sin being committed is high.