Retroactively turning down an accepted offer to a professional program from one school in favour of an offer from another school? If I accept an offer to a professional program from one school (e.g., law, medicine, pharmacy, etc.) and then later get an offer to a better program from a different school, can I retroactively turn down the first offer to accept the second?

Both schools are in Canada, but answers relevant for US schools may also be useful.

I'm actually asking for my brother. The problem in his situation is that the acceptance deadline for one school is after the offer date for another ("better") school. The first school has refused to extend the deadline and the second school has refused to give early notification that an offer is pending.

I am hesitant to say the exact type of program because I don't want to expose his identity to anyone making a decision regarding his admission.

The following question is about grad school, not professional programs, so I'm unsure if the answers apply.
Is it legal to withdraw a signed offer letter from grad school?
The first school won't like it, but there would be nothing to stop your brother from backing out of the first offer and accepting the second offer, unless the schools work closely together to prevent this from occurring, which seems highly unlikely, especially because their notification dates differ so greatly.

If your brother is accepted to the second program, the most courteous way to inform the first program would be:


as quickly as possible, so they can accept someone from their waiting list or otherwise make use of the information.
without insulting the first program.


For example, he might write something like:


  I realize that, as grateful as I am for admission into your program, pursuing it would not be the right thing for me to do at this time and that I should not have accepted your offer.  I am very sorry that I have to withdraw my acceptance.  I hope it is not too late for you to offer the place to a student who is a better fit for your program.