The socialite-turned-mogul was on Capitol Hill Wednesday to testify about the abuses of children in the system -- relating it to some of her own experiences -- before diving into how she's trying to solve the issues.

Check out the clip ... Hilton mentions she's helped outlaw several harsh disciplinary practices, including restraint and seclusion, and she's also pushed for increased site visits to hold those running foster homes accountable.

But, Paris says she also has hopes at the federal level ... saying she wants Congress to reauthorize Title IV-B -- a federal fund for states' child welfare programs -- and to pass the Stop Institutional Child Abuse Act.

The bill was introduced more than a year ago -- it's yet to be passed by the House or Senate -- and would establish a more centralized system for tracking and implementing youth placement.

Of course, that's only a small part of Paris' testimony ... 'cause she once again detailed the physical, emotional and sexual abuse she says she endured while at a youth residential treatment facility.

Paris has previously accused Utah's Provo Canyon School of being more like an obedience camp where she says students were locked up for 20 hours at a time and regularly demeaned by the staff.

While not a child welfare residence, Paris says she sees a parallel between her trauma and what she says many kids in the system face.