If his disability pension is social security disability, reported on form SSA-1099; the answer is still no, you can't claim him, but for a different reason.
Social security doesn't count as income, for the dependent income test, but social security money he spends on homself does count as support not provided by you, for the support test. Money he puts into savings & investment does not count as support he spent on himself.
The IRS has a worksheet that can be used to help with the support calculation. See: <a rel="nofollow" target="_blank" href="
http://apps.irs.gov/app/vita/content/globalmedia/teacher/worksheet_for_determining_support_4012.pdf"...> The support value of a home is the fair market rental value, divided by the number of occupants.
A person can still be a dependent, if not a Qualifying Child, if he meets the 6 tests for claiming a dependent:
1. Closely Related OR live with the taxpayer ALL year
2. His/her gross taxable income for the year must be less than $4,050 (2016)
3. The taxpayer must have provided more than 1/2 his support
In either case:
4. He must be a US citizen or resident of the US, Canada or Mexico
5. He must not file a joint return with his spouse or be claiming a dependent of his own
6. He must not be the qualifying child of another taxpayer
