word choice - Present or Past tense to describe a past condition which is still present?

Scenario: My friend John has a personality disorder, intensely paranoid for example.

Can I say:

There were three events last year that told me John had a problem.

or can I say:

There were threee events last year that told me John has a problem.

Answer

I agree with mgkrebbs in the case of storytelling. In conversation, however, if I say:

There were three events last year that told me John had a problem.

I am implying that he had a problem last year but that the problem is no longer present. If I say:

There were three events last year that told me John has a problem.

I am implying that the problem existed last year and continues into the present.

Might I also suggest the following (assuming the problem still exists):

Three events last year told me John has a problem.