State appellate court unreasonably applied clearly established U.S. Supreme Court precedent when it found that trial counsel made a reasonable tactical decision to not obtain a psychological evaluation of a fourteen-year-old defendant. Weeden was convicted of attempted robbery and felony murder and sentenced to twenty-nine years to life in prison for her role in a robbery that occurred when she was fourteen. She was not present at the scene of the crime, and the prosecution’s case rested on evidence of her role in planning and facilitating the robbery. Weeden moved for a new trial and argued that her trial counsel was ineffective by failing to investigate or present psychological evidence. She included a report from a psychologist who opined that it was “extremely unlikely” that Weeden would intend to commit robbery or knowingly participate in one. The trial court denied the motion. After exhausting state court remedies, Weeden filed a federal habeas petition, which the district court denied. She appealed. Held: Reversed. Clearly established Supreme Court precedent provides that counsel has the duty to make reasonable investigations or to make a reasonable decision that makes particular investigations unnecessary. Here, the state court did not identify any “reasonable decision” made by trial counsel that rendered investigation of psychological evidence “unnecessary,” and instead found that counsel’s choice not to investigate psychological evidence was a sound “tactical decision” because counsel feared the results of an expert evaluation might undermine his trial strategy. However, counsel’s investigation must determine trial strategy, not the other way around, and counsel cannot justify a failure to investigate by invoking strategy. Given that Weeden’s mental condition was an essential factor in deciding whether she had the required mental state for the crime and the Supreme Court’s repeated recognition that the mind of a fourteen-year-old is markedly less developed than an adult, Weeden’s counsel had a duty to investigate psychological evidence in forming his trial strategy, and the state court’s finding to the contrary was unreasonable.

Petitioner was prejudiced by counsel’s deficient performance, requiring reversal. Because the state appellate court did not make a finding on prejudice in Weeden’s case, the Ninth Circuit addressed the issue de novo. Counsel’s deficient performance justifies habeas relief only if there is a “reasonable probability” that the jury would have reached a different result if adequate representation had been afforded. Here, Weeden’s mens rea was a critical issue at trial. Because Weeden was not at the crime scene and did not personally commit the robbery or the murder, the state’s evidence of her intent was presented through testimony by others about what she said and text messages sent months after the events at issue. This evidence did not present “the kind of critical insight into the effect of Weeden’s youth on her mental state” that the expert’s conclusions provided. The court also found the fragmented verdict (Weeden was acquitted of attempted murder) was an additional indicator of prejudice. Under these circumstances, there was a reasonable probability the jury would have reached a different result had the expert’s opinion been presented at trial. The court also noted that to the extent the state court made a finding on prejudice by speculating that the jury “might have” reached the same result, AEDPA deference still would not apply because the state court applied the wrong legal standard.

The full opinion is available on the court’s website here: http://cdn.ca9.uscourts.gov/datastore/opinions/2017/04/21/14-17366.pdf