Sen. Richard Blumenthal (D-Conn.) called on U.S. Soccer president Sunil Gulati to "actually conduct a thorough investigation" into women's national team goalie Hope Solo and domestic violence accusations against her.

Blumenthal also suggested that U.S. Soccer "reconsider Hope Solo's position as an active member of Team USA," in a letter dated Thursday.

"Domestic violence is unacceptable," the letter said, "particularly for an athlete representing the United States of America on the global stage."

Outside The Lines, with new court documents and an interview with Solo's half-sister Teresa Obert, took an in-depth look into Solo's actions that led to her arrest in June 2014 after an altercation with Obert and Solo's teenage nephew.

Police said Solo was belligerent and insulting toward officers during her arrest, and had been drinking. Domestic abuse charges were dropped in January on procedural grounds, but prosecutors filed an appeal with the Superior Court of Washington. They are scheduled to file their argument by July 13, with the defense due to respond by Aug. 10. Oral arguments are scheduled for Sept. 11.

In the letter, Blumenthal wrote:

"Last year, I criticized the NFL for failing to adequately punish domestic violence in the wake of a two-game suspension given to Ray Rice. It is distressing that after so many months of national dialogue on the issue, we find ourselves at square one in the Hope Solo situation. If the Outside the Lines reports are correct, U.S. Soccer's approach to domestic violence and family violence in this instance is at best superficial and at worst dangerously neglectful and self-serving.

"I urge U.S. Soccer to conduct a thorough investigation into this incident -- an inquiry that includes a comprehensive review of police reports and interviews of the alleged victims. In the interim, U.S. Soccer should at least articulate an explanation for Hope Solo's position as an active member of Team USA. As boys and girls tune in to Friday's game, watching the women on TV as role models, what is the message of starting Hope Solo at goal?

"Domestic violence and family violence are an horrific scourge that happens behind closed doors every day in this country. Regardless of whether the violence is a man striking a woman, a woman striking a man, or same-sex violence, it is unacceptable. Domestic violence is intolerable particularly for an athlete representing the United States of America on the global stage.

"Soccer today faces huge challenges as the FIFA scandal unfolds. Hope Solo continuing to play goalie for Team USA, just months before she will appear in court to face domestic violence charges, raises troubling questions about the state of the game."