In general, you do not have a duty to disclose facts about a situation to a governing authority. Despite what we are taught about being good citizens, in most cases you are not required to "tell on someone" who is engaged in an improper course of conduct.
However, in some cases you can have an obligation to disclose facts. It appears that PADI may have a rule that requires certain disclosures, so consider this: if you become a PADI DM, and you know that another DM did not meet standards, you may have an obligation to report him or face consequences yourself. Admittedly, that's speculation on my part, since I do not have access to the PADI standards and regulations.
If you need other reasons to help you convince your fellow candidate that he shouldn't falsify his application or logbook, here are a couple others:
1. Professional liability insurance. He may be required to certify that you have made X number of dives. If he lies, he may get coverage, but the insurance company may cancel his policy or deny coverage in the event of an incident.
2. Personal liability. If he is sued because of an accident or other problem, someone WILL investigate his diving history. If it comes out that he falsified his logs to enter DM training, that fact could damage his case. Additionally, it is possible that such conduct could be considered grossly negligent, reckless or even intentionally wrongful, and could expose him to a greater award against him.
3. Dive shop relations. If the LDS finds out that he lied about logged dives, he's going to upset them. It may also cause the LDS problems with their own relationship with PADI or insurers.
I have thought of doing DM training as well. However, I have not been able to find any of my old logs. I have been diving for 15 years, and the LDS wouldn't even question whether I have sufficient dives to start or complete training. My personal policy is, though, that unless I have a piece of paper with a legitimate signature or a computer log entry, I don't have a dive that I can count toward prerequisite dives. That's just my policy based upon my assessment of the risks involved, to say nothing of personal integrity.
Others have recommended confronting the candidate first, then speaking with the LDS if the person won't come clean. That's a good idea. If you feel comfortable diving with this person (which I sort of doubt), you might offer to help them log good quality dives. Good luck.
However, in some cases you can have an obligation to disclose facts. It appears that PADI may have a rule that requires certain disclosures, so consider this: if you become a PADI DM, and you know that another DM did not meet standards, you may have an obligation to report him or face consequences yourself. Admittedly, that's speculation on my part, since I do not have access to the PADI standards and regulations.
If you need other reasons to help you convince your fellow candidate that he shouldn't falsify his application or logbook, here are a couple others:
1. Professional liability insurance. He may be required to certify that you have made X number of dives. If he lies, he may get coverage, but the insurance company may cancel his policy or deny coverage in the event of an incident.
2. Personal liability. If he is sued because of an accident or other problem, someone WILL investigate his diving history. If it comes out that he falsified his logs to enter DM training, that fact could damage his case. Additionally, it is possible that such conduct could be considered grossly negligent, reckless or even intentionally wrongful, and could expose him to a greater award against him.
3. Dive shop relations. If the LDS finds out that he lied about logged dives, he's going to upset them. It may also cause the LDS problems with their own relationship with PADI or insurers.
I have thought of doing DM training as well. However, I have not been able to find any of my old logs. I have been diving for 15 years, and the LDS wouldn't even question whether I have sufficient dives to start or complete training. My personal policy is, though, that unless I have a piece of paper with a legitimate signature or a computer log entry, I don't have a dive that I can count toward prerequisite dives. That's just my policy based upon my assessment of the risks involved, to say nothing of personal integrity.
Others have recommended confronting the candidate first, then speaking with the LDS if the person won't come clean. That's a good idea. If you feel comfortable diving with this person (which I sort of doubt), you might offer to help them log good quality dives. Good luck.