We were taught that we should not use contraction like she's or she'd in formal writing.
However, a newspaper editorial uses these. Is the above rule not widely accepted? Or newspaper editorials are not formal writings?
Here is from the New York Times editorial "Mrs. Clinton, Show Voters Those Transcripts".
Public interest in these speeches is legitimate, and it is the public — not the candidate — who decides how much disclosure is enough. By stonewalling on these transcripts Mrs. Clinton plays into the hands of those who say she's not trustworthy and makes her own rules. Most important, she is damaging her credibility among Democrats who are begging her to show them that she'd run an accountable and transparent White House.