What happened with Mr. Clutter before he died and how is it both ironic and tragic

Mr. Clutter had just had a phyiscal examination for a life insurance policy. Ironically, he was killed within hours of signing the policy.

Then, responding to questions, he said no, neither of the women had been “sexually molested,” and no, as far as was presently known, nothing had been stolen from the house, and yes, he did think it a “queer coincidence” that Mr. Clutter should have taken out a forty-thousand-dollar life-insurance policy, with double indemnity, within eight hours of his death.