United States: A man walked into Robert H. Schuller's church, the Crystal Cathedral, and shot himself in front of a cross.
Betty Spicer, a volunteer usher at the famous sanctuary, said she greeted Smick when he entered. She said he handed her a folded note with two cards inside as the man told her:You may want this.
Spicer said he then walked to the foot of the cross. She and Yvette Manson, another volunteer, said they thought Smick was praying when they heard a pop.
The man used a semiautomatic handgun, said police Lt. Dennis Ellsworth.
At the same time, church volunteers were telling a group of visitors about the church's suicide prevention programme, which is based on prayer rather than anything with any basis in the real world.
Man kills self in SoCal televangelist's cathedral—International Herald Tribune, 19th February 2009 (thanks, Pastor Best OPI),

Considering that some Pagans do pray (to many deities), I'm surprised no one's called bollix on that.
Depending on how prayer is used, it could hurt or help the situation. A mantra of "Please don't let me kill myself..." will constantly keep in the forefront of the suicide's mind that they do want out. A mantra of "Help me to find something else to focus on..." would more likely help. I should know that it was a hell of a lot easier to let go of my obsession of ME and everything ME during my suicidal phase by seeing that that there were other people on this planet. That's called growing up.
Since not all suicides are depressed (although a majority are), but can be a call for getting attention--forget help, typical therapy-until-drugs-are-given may make them more likely to kill themselves. It is well known that many kids become more suicidal on the drugs that are supposed to help them.
Plus, even if it doesn't really work, it would still work for about 15% of potential suicides, just by being a placebo effect.