Why did reporter bob woodward become interested in what appeared to be a routine burglary?

For the answer to the questions above, because one of the 5 defendants caught his attention. One of them was James McCord who answered that he was retired from government service (CIA) and ask himself on why was a former CIA agent involved in what seemed to be just a burglary.

Woodward and his colleague, Carl Bernstein investigated this. They uncovered a something that triggered a constitutional crisis which forced Nixon to resign to the office.