She and her husband, then-Prince George's County Executive Jack Johnson, were arrested last month on charges including evidence tampering.
Leslie Johnson was sworn into the City Council on Monday, against the wishes of five current council members.
Although Johnson will not be serving on any committees, she is still allowed to attend committee meetings. The county charter also allows her to maintain some voting rights.
The measure was taken to "avoid any appearance of impropriety," said Council Chair Ingrid Turner.
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