The Defense Department's latest report showing progress in curbing sexual assaults was deeply flawed and failed to account for attacks on military spouses and civilian women at bases nationwide, Sen. Kirsten Gillibrand, D-N.Y., charged Monday.

"The more we learn, the worse the problem gets," Gillibrand said in releasing an analysis by her office of limited data provided by the military on 107 cases at the Army's Fort Hood in Texas, Naval Station Norfolk in Virginia, the Marine Corps' Camp Pendleton in California and Wright-Patterson Air Force Base in Ohio.

Gillibrand's review of the cases showed "a high prevalence of sexual assault against civilian women near bases and civilian spouses of service members -- two survivor groups not counted in DoD prevalence surveys."

The senator's latest charges followed the release last Friday of DoD's Sexual Assault Prevention and Response Office' (SAPRO) annual report on sexual assaults and harassment in the military.

The Defense Department report showed that sexual assaults reported by military personnel numbered 6,131 in 2014, an increase of 11 percent over the previous year.

However, a biannual Rand Corp. survey that was part of the report estimated that 18,900 military personnel were victims of "unwanted sexual contact" in 2014, compared to about 26,000 in 2012, which would be a decrease of about 27 percent.

Gillibrand charged that military spouses and civilian women who live or work near military bases "remain in the shadows" because neither group is counted in the SAPRO reports.

In response, the Pentagon released a statement saying: "The department does not have standing authority to survey non-DoD civilian populations. However, federal surveys have found that the prevalence of sexual assault for non-DoD civilian women is statistically the same for military women and female spouses of military members."

Immediately after the release of the DoD report, Sen. John McCain, R-Ariz., chairman of the Senate Armed Services Committee, said the report showed that the military was making "critical progress" in curbing sexual assaults but added that "much more needs to be done."

Gillibrand said that her office in February 2014 asked for all files pertaining to the investigation and adjudication of sexual assault cases from 2009 through 2013 at the four bases – Hood, Pendleton, Norfolk and Wright-Patterson. Instead, DoD only provided the 107 case files from 2013 at the four bases, Gillibrand said.

The analysis of the 107 cases by her office "reaffirms a lack of trust in the military justice system as nearly half of the survivors in the cases reviewed declined to move forward after initially filing a report," Gillibrand said.

The senator's office said that even when cases did proceed, just over 20 percent went to trial and only 10 percent of all cases resulted in a sexual assault conviction with penalties of confinement and dishonorable discharge.

The cases that did proceed to trial but failed to obtain a sexual assault conviction typically resulted in more lenient penalties, such as a reduction in rank or docked pay, Gillibrand's office said.

"These 107 files are a snapshot of the thousands of estimated cases that occur annually -- the latest projection for 2014 alone is 20,000 cases of sexual assault and unwanted sexual contact," Gillibrand said in a statement.

"What we've found are alarming rates of assault among two survivor groups not routinely counted in DoD surveys, survivors declining to move forward with their cases and very low conviction rates," she said.

"Even with the much-lauded reforms, the system remains plagued with distrust and simply does not provide the fair and just process that survivors deserve," Gillibrand said.

In response to Gillibrand's charges on underreporting, Laura Seal, a DoD spokesperson, said that the trends in the DoD report showed that in FY2014 there were "indications of increased confidence in our military justice system. Reporting is up: We estimate that one in 10 military victims reported in FY2012, and one in four military victims reported in FY2014."

Gillibrand, a frequent critic of the military's response to sexual assaults, sponsored legislation last year calling for the removal of sexual assault cases from the chain of command and giving authority for handling the cases to independent military prosecutors.

The legislation failed to reach the Senate floor for a vote but Lauren Passalaqua, a spokesperson for Gillibrand, said that the senator may re-introduce the legislation this fall.

-- Richard Sisk can be reached at richard.sisk@military.com