The Home Secretary told the House of Commons she had "long been concerned about the use of stop and search".
Theresa May said: "While it is undoubtedly an important police power, when it is misused stop and search can be counter-productive
"First, it can be an enormous waste of police time. Second, when innocent people are stopped and searched for no good reason, it is hugely damaging to the relationship between the police and the public. In those circumstances it is an unacceptable affront to justice."
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David Cameron has raised concerns after figures showed 100 babies spent time living behind bars last year.
About 124,000 patients had to wait for at least 12 hours in accident and emergency departments last year, according to an investigation.
Today's rain will clear into the North Sea tonight, but winds will stay strong, with showers feeding in to the north and west.