Yes, you may own more than one life insurance policy.
When you apply for life insurance the insurance company usually asks on the application if you own other life insurance, and how much life insurance coverage you already own.
The insurance company doesn't want you to be over-insured, which may lead to a risk of you possibly taking your life, if you were worth much more dead than alive.
Life insurance policies do have a suicide clause that excludes coverage for suicide, however, that is if the suicide takes place usually within the first two years of owning the policy. So, someone might be able to commit suicide after two years and the death benefit would be paid out to the beneficiary.
However, most life insurance companies may allow you to own 10 to 20 times your annual income in life insurance.