WASHINGTON — The Supreme Court on Wednesday refused to require courts to examine suggestive eyewitness evidence with extra care unless it was produced by police misconduct.

The decision, by an 8-to-1 vote, effectively ruled that the only reason to let judges rather than jurors assess the reliability of eyewitness evidence was to deter police misconduct.

Justice Ruth Bader Ginsburg, writing for the majority, said there was no reason to treat most eyewitness evidence differently from other potentially flawed evidence. “The jury, not the judge, traditionally determines the reliability of evidence,” she wrote.

“The potential unreliability of a type of evidence does not alone render its introduction at the defendant’s trial fundamentally unfair,” she added, noting that the court had refused to require special procedures for, for instance, testimony from “jailhouse snitches.” Cross-examination, jury instructions and the usual rules of evidence are sufficient safeguards, she wrote.